> Thus you have the power to fix it, at least on the small scale, and yet I haven't heard of a single person who holds these views even attempting to do so.

That could be because they aren't trying to help -- or it could be because of the difference between "I haven't heard of ..." and "I know they aren't". What reason do you have to think that it's the former?

Specifically, do you know whether the people you're talking to give money to charities that try to help poor people? (Whether in the US or abroad in poorer places where one can do more good per dollar.)

In any case, I think your criticism is logically unsound. That is, you can't get from "X doesn't spend his own money trying to change Y" to "X is insincere when saying Y should be changed", and still less to "Y should not in fact be changed".

Let's take a concrete example. X has an income of $100k/year and says that incomes at that level should be taxed an extra $1k/year in order to help the poorest people in society. X could find a poor person and give them $1k/year, but doesn't. Does this show that X doesn't really mean what he says?

Nope. Let me sketch for you a position X could (somewhat plausibly) hold. X is a kinda-utilitarian. He wants to maximize overall well-being, except that he cares (let's say) 100x more about his own well-being than any other person's. Of course there's more to well-being than money, but let's say that (in X's opinion) income makes a contribution to well-being that's proportional to log(annual_income+$5k) -- I remark that this sort of dependence of utility on money is very widely used, and isn't some sort of unnatural cherry-picked thing chosen to get the results I want. And let's suppose that X is in the US, that the US's labour force is 150M people, of whom 20% are at or above that $100k/year threshold and 10% are at or below let's say $12k/year. X's proposal is to take $1k/year from each of the 30M comfortably-off people and give $2k/year to each of the 15M poor people.

So, how do the utility calculations stack up? For the "global" change: 30M people go from log(105k) to log(104k) and 15M people from log(17k) to log(19k). (Actually, some of the 30M will be on higher incomes and lose less utility, and some of the 15M will be on lower incomes and gain more utility.) So each of the comfortable people loses 0.0096 units of utility and each of the poor people gains 0.111 units. Since 0.111 is much more than twice 0.0096, this is a big win overall. Of course we also need to count X's loss 100x more -- but that's completely swamped by the millions of other people affected.

But for the "personal" change where X alone makes the sacrifice: he goes from log(105k) to log(104k), losing 0.0096 units ... but remember that he counts himself 100x more, so he actually loses 0.96 units. That's much more than the 0.057 units his $1k could provide to a poor person.(Not 0.111 -- remember that the plan was to redistribute two lots of $1k/year to each poor person, but there's only one X.)

A society all of whose comfortably-off people think as X does would choose to make that change, making the poor richer and the rich poorer for an overall benefit; all of them would agree with this despite caring 100x more about themselves than about each other person, because there are so many other people. But a single X would not choose to make the donation on his own. No inconsistency or insincerity required.

(Well, maybe there's a little inconsistency, to the following extent: someone whose values are exactly as I described would in fact support more redistribution than the proposal above. Note that this goes in exactly the wrong direction to help your argument.)

The numbers above are not cherry-picked for anything other than plausibility and simplicity of calculation, and in particular I picked them all before doing any actual utility calculations. Most people are not exactly "weighted utilitarians" like X, but I think X's weighted utilitarianism is a reasonable -- though of course imperfect -- approximation to many people's moral values. Logarithmic dependence of utility on money is a very standard assumption, with a pedigree going back to the 18th century and widespread usage continuing to the present day.