Morality means different things to different people. Some even believe that freeing a slave was immoral because it deprived his owner of an asset.

Only if you forget that money is supposed to function as a lubricant for satisfying needs and think that it is somehow a good reflection of someone or something's worth to society.

Reducing accumulation of money (by means of for instance a wealth tax) is incredibly important to keep the economy as a whole going and to maximize the needs satisfied, but if you only think in terms of "but poor people don't deserve free money!", you miss this point and say dumb things like "a wealth tax is deeply immoral".