It's a very complex topic, but to put it as succinctly as possible, the key difference is between self-declared atheists who truly appear as such, and those who insist on their atheism, but various quasi-religious elements are nevertheless clearly discernible in their lives and worldviews (to the point where I would dispute whether it makes sense to exclude them from the general definition of "religion").
Overall, my impression is that among the atheists found in North America, those of the latter kind are far more frequent and prominent compared to the post-Communist Eastern Europe, with Western Europe being somewhere in-between, but closer to North America. (Of course, these large geographical regions contain parts of greatly different religiosity, but what I write tends to be true for the local atheists found there regardless of their percentage in the local population.) Why this is so, and what exact quasi-religious elements are commonly seen among different sorts of self-declared non-religious people, are complex and fascinating questions, which are however difficult to discuss because they touch on many ideologically sensitive issues.
When I read people's writings on all sorts of issues, I can usually discern the two types of atheists pretty quickly and reliably, and based on your comments I've read in this thread and elsewhere, you do seem to belong to the true sort like you declare. Assuming you're writing from somewhere in Europe or the Anglosphere, as most people here are, this by itself places a significant probability on you being Eastern European, and more specifically from one of the less religious EE states, like Hungary, Czech Republic, or various former Soviet republics (as opposed to much more religious places like Poland or Croatia). Considering that your username is the word for "piglet" in several (but not all) Slavic languages, one of which is Czech, this seemed like a high-probability guess. Also, some additional evidence is that your English is excellent but still a little bit Slavic-souding, and your writing has a slight and vague quality typical of Central Europe that is very hard to explain. (By the way, if you're curious, I'm Croatian.)
Overall, my impression is that among the atheists found in North America, those of the latter kind are far more frequent and prominent compared to the post-Communist Eastern Europe
This is probably in agreement with my anecdotal experience, but I haven't realised it explicitly before. What I can think about at the moment is the webpage Daylight Atheism, whose author had spent a lot of time defending the concept of atheist spirituality (e.g. here), and there was usually surprisingly little opposition in the comments.
...your username is the word for "p
Fifteen thousand years ago, our ancestors bred dogs to serve man. In merely 150 centuries, we shaped collies to herd our sheep and pekingese to sit in our emperor's sleeves. Wild wolves can't understand us, but we teach their domesticated counterparts tricks for fun. And, most importantly of all, dogs get emotional pleasure out of serving their master. When my family's terrier runs to the kennel, she does so with blissful, self-reinforcing obedience.
When I hear amateur philosophers ponder the meaning of life, I worry humans suffer from the same embarrassing shortcoming.
It's not enough to find a meaningful cause. These monkeys want to look in the stars and see their lives' purpose described in explicit detail. They expect to comb through ancient writings and suddenly discover an edict reading "the meaning of life is to collect as many paperclips as possible" and then happily go about their lives as imperfect, yet fulfilled paperclip maximizers.
I'd expect us to shout "life is without mandated meaning!" with lungs full of joy. There are no rules we have to follow, only the consequences we choose for us and our fellow humans. Huzzah!
But most humans want nothing more than to surrender to a powerful force. See Augustine's conception of freedom, the definition of the word Islam, or Popper's "The Open Society and Its Enemies." When they can't find one overwhelming enough, they furrow their brow and declare with frustration that life has no meaning.
This is part denunciation and part confession. At times, I've felt the same way. I worry man is a domesticated species.
I can think of several possible explanations:
1. Evo Psych
Our instincts were formed in an ancient time when not knowing the social norms and kow-towing to the political leaders resulted in literal and/or genetic extinction. Perhaps altruistic humans who served causes other than our own were more likely to survive Savannah politics.
2. Signaling
Perhaps we want to signal our capability to put our nose to the grindstone and work for your great cause. Hire me!
3. Memetic Hijacking
Growing up, I was often told to publicly proclaim things like "Lord, I am not worthy to receive you." Perhaps spending years on my knees weakened my ability to choose and complete my own goals.
4. Misplaced Life Dissatisfaction
Perhaps it's easier for an unemployed loser to lament the meaninglessness of life than to actually fix his problems.
The first theory seems plausible. Humans choke to avoid looking too good and standing out from the pack. Our history is full of bows, genuflects and salutes for genocidal a-holes and early death for the noble rebels.
The second seems less likely. Most similar signaling makes people appear as happy, productive workers, not miserable, tortured artists.
The third and fourth explanations fit well with my experiences. My existential angst didn't fade until I purged my brain's religious cobwebs and started improving my life. These things happened at about the same time, so I can't tell whether three or four fits better.
I'd welcome anecdotes in the comments, especially from people raised in a secular environment. If you don't grow up expecting the universe to have meaning, are you ever dissappointed to find it is meaningless?
But no matter the cause, "What is the meaning of life?" is a question that should be dissolved on sight. It reduces humanity to blinding subservience and is an enemy to our instrumental rationality.
Building instrumental rationality may not be the reason why we're on this planet, but it it is the reason we're on this website.