No, it's not stupid, you're right. It's just one of the differences between underdeveloped faith and faith that has actually been thought through.
Either what we call God has a plan and praying asking for things has no effect other than consolation of ourselves and expression of our feelings, or what we call God has a plan that we take control and responsibility for our own lives and God is generally far less concerned with the corporeal world than many people of faith believe God to be. Frankly, either way, petitionary prayers are clearly fruitless IMO. Not to say that they're "wrong" per se, but only to say that I don't think one should not expect them to be answered. Incidentally, I believe in the latter of the two possibilities I presented.
(This is, of course, ignoring the "God doesn't exist" and "religion is a crutch for the weak" argument that I'm sure some of our atheistic zealots will be more than happy to point out in response to this thread later on
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