I have often been charitable out of a desire to see my charity make a positive difference in a persons life. When they treat my charity like it is an entitlement, I might see the positive difference I desired but if I see that and the recipient is obviously grateful and seemingly inclined to pay it forward then I am motivated to increase my charity because it feels so good.
I think that everyone, even the most charitable do everything they do out of self-interest. You said “ More just the urge to help out, to level things up a bit” I think in your case the “to level things up a bit” either reduces some guilt you hold for your possible privilege or it is a “Donor’s High” the feel good feeling you get from doing good. Well, if your charity produces gratitude then that “Donor’s High” is some little bit higher. I am sure there are other possibility but they all sort of track together.