Actions which increase utility but do not maximise it aren’t “pointless”. If you have two charities to choose from, £100 to spend, and you get a constant 2 utilons/£ for charity A and 1 utilon/£ for charity B, you still get a utilon for each pound you donate to B, even if to get 200 utilons you should donate £100 to A. It’s just the wrong word to apply to the action, even assuming that someone who says he’s donated a small amount is also saying that he’s donated a small proportion of his charitable budget (which it turns out wasn’t true in this case).
Actions which increase utility but do not maximise it aren’t “pointless”. If you have two charities to choose from, £100 to spend, and you get a constant 2 utilons/£ for charity A and 1 utilon/£ for charity B, you still get a utilon for each pound you donate to B, even if to get 200 utilons you should donate £100 to A. It’s just the wrong word to apply to the action, even assuming that someone who says he’s donated a small amount is also saying that he’s donated a small proportion of his charitable budget (which it turns out wasn’t true in this case).