Anne,
If X=HIV victims in Chad, Y=malaria victims in Gabon, to a pretty good approximation you do that every time you donate to a charity supplying antiretrovirals in Chad rather than one distributing bed-nets in Gabon. Time and other resources are scarce for each of us, and we have to deal with it.
Michael,
You 'expect' to live forever, i.e. consider it more likely than not? Outside of quantum immortality and similar views about other multiverse concepts, that seems to go beyond the evidence. Unless thermodynamics can be circumvented we will almost certainly die for lack of resources, even if we don't suffer aging or succumb to existential risks or other sudden dooms.
"Belief is not suitable as any kind of evidence when more-direct evidence is available, yet people tend to reject direct evidence in order to conform with the beliefs of others."
Caledonian, this is just wrong. Our ability to interpret evidence is not infallible, and is often fallible in ways that are not perfectly correlated across individuals. So even if we share the same 'direct evidence' as other observers of equaly ability their beliefs are still relevant.