There's a difference between toughing out the rest of the match and just being a masochist doofus and sticking with something that ain't working. Our team had less people than the other one, less experienced players and we were basically just walking out of spawn and instantly getting killed evey ten seconds. That isn't a game, and if the other team doesn't like it then they can find opponents who are on their level. I don't know why someone would find it fun to just spawncamp the other team and roll over people who are obviously way less good at the game than them, it's like bragging that you can beat a four year old at 1v1 basketball.
Also were *you* having fun? One round you built an engineer nest right outside our spawn and in the time it took you to upgrade everything the other team capped the first two points. I don't see what's fun about hitting buildings with a wrench for three minutes while your team gets rolled.
I genuinely don't have a problem with losing games. It doesn't have to even be close, there just has to be some sense of minimal accomplishment. Like, oh, we at least held out for a bit. Not a non-stop roll by the other team.