Yes. Yes I do. Getting the crap kicked out of you on your home field, in front of your home crowd hearing boos absolutely affects players. I would imagine if one were to ask most high end athletes they would say this bothered them. Most of the pro athletes I know are uber competitive and remember games years later. Ask the players on the losing end of our shellacking of the Raiders in 1990 51 to 3.
However, I agree with your overall point that there is no need to feel sorry for a multimillionaire playing a game as a full time job.