It’s not altruism, it’s just that I’d need to actively chase more pay to get it. And I’m not in a position where I want to (don’t want to switch jobs etc). Marginal taxes are also quite high (over 50%) so there are diminishing returns.

For reference I make around $70k as a senior type eng. Not huge but the “ceiling” (for cash comp) if I switched jobs 10 times and ended up at a very well paying job in the end would be 20-40% more - which is 10-20% net!