I don't understand this. Why should my utility function value me having a large income or having a large amount of money? What does that get me?

I don't have a good logical reason for why my life is a lot more valuable than anyone else's. I have a lot more information about how to effectively direct resources into improving my own life vs. improving the lives of others, but I can't come up with a good reason to have a dominantly large "Life of leplen" term in my utility function. Much of the data suggests that happiness/life quality isn't well correlated with income above a certain income range and that one of the primary purposes of large disposable incomes is status signalling. If I have cheaper ways of signalling high social status, why wouldn't I direct resources into preserving/improving the lives of people who get much better life quality/dollar returns than I do? It doesn't seem efficient to keep investing in myself for little to no return.

I wouldn't feel comfortable winning a 500 dollar door prize in a drawing where half the people in the room were subsistence farmers. I'd probably tear up my ticket and give someone else a shot to win. From my perspective, just because I won the lottery on birth location and/or abilities doesn't mean I'm entitled to hundreds of times as many resources as someone else who may be more deserving but less lucky.

With that being said, I certainly don't give anywhere near half of my income to charity and it's possible the values I actually live may be closer to what you describe than the situation I outline. I'm not sure, and not sure how it changes my argument.