I've done some studying, learned about ranges for stealing, raising, calling, positional play etc. but I get bored with all that theory. I don't really care about my odds and outs and I probably make bad plays if you consider my pot odds.
However, I've made tons of money over the years, mostly playing tournament poker, Sit-n-Go's and scheduled tournaments (MTTs) where you cannot choose who you play with.
SnGs When you play a lot, you learn to know the regulars. You will know the winning players and the rest are either new players or losing players. You will also learn their shove/fold ranges. The more you play, the more accurate information you get.
MTTs You cannot walk away from the table and move your chips to another table. If it's a slow tournament, you're stuck with whoever sits at your table, possibly until the end which might be 7-8 hours away. That's a lot of time to get reads on your opponents - which I consider one of my strengths.
I once tried some poker tracking software (30 days for free) and saw that the red line (I'm not 100% sure about the color), chips won without showdown, was constantly going up, while the other line, chips won at showdown went up and down, maybe slightly more up than down but it looked very random.
So is there a reason why I (or anyone else) should get my poker math right all the time? To me it seems that you can get quite far just by learning to read your opponents: seeing when they're ready to fold and when they're bluffing - regardless of any cards that anyone holds. I'd rather work on reading my opponents better unless I find out that I'm losing lots of equity not getting my pot odds right.