Are your opponents wrong if they get upset by the fact that you don't concede, yet you still get mad that they have the win and don't just win? If you get upset with that kind of thing, just concede. Or don't get upset and hope for your opponent to have a misstep and pass through their attacks.
Either way, your opponent is just playing their game, as you are. If you think you are wasting your time, just concede.
BTW: I am almost sure that the loss of focus you have when you get upset with that kind of thing lowers your % more than the chance of your opponent have a brain fart AND you still win the game after that. And not to mention quality of life(!!). Getting salty is bad only for you. Relax, take it easy.