... can't think of one good reason to "not care" about rake ...

Rake is taking bb's out of every pot... meaning that your winrate must be significant just to "break even". The higher the rake, the more it cuts your winnings.

If you play a pot for 100 bb, and the rake is 5%, then you just lost 5 bb to the house. Losing 5 bb an hour (assuming you are involved in 1 big pot an hour) is a HUGE hit to your winrate. EVEN IF you're crushing your stakes for 20bb/100, that's going to be at least a 10% hit to your winrate, probably closer to 25%.

NOW... once you've decided that a given rake structure is acceptable, then there's no reason to dwell on it. But NOT CARING is out of the question... to me, at least.