Yeah he shouldn't have been on the field in the first half. But I don't have a problem with him quitting at halftime. When you're washed up, it's time to go home. What is really to be gained by him staying there? To stand there after quitting?
When dude quit when I was in high school, the coach made him go sit in the stands and sit at the back of the bus on the ride home. Difference is this is a grown man and they were playing in Buffalo. Some people are way too focused on punishing adults for personal decisions that don't hurt anyone, and ultimately this is more than just a business, we are talking about a game that can put a player in a wheelchair for the rest of their life.