Why can't it all be real? Genuine emotion before and genuine emotion after? You mention WWE, but all sports have this. Boxing matches end like that all the time.
I have no problem with fighters putting it all behind them after the fight. It doesn't make them any less real, nor the pre-fight emotions any less real. Even me as a fan have completely different emotions before and after watching fights. Why shouldn't the fighters?
The point being, that it isn't genuine emotion before, in all cases.
Sometimes they legitimately put the beef behind them, after a genuinely heated pre match build up, and that's totally cool. However, sometimes they talk all this fake crap about each other, go out and have a mediocre emotionless fight, then have a hugathon at the end.
It grates on me, the more I see it.