So whats the deal with people who intentionally feed?

About 1 out of 3 games I get the person who loses lane or thinks the teams gone down hill and starts yoloing and intentionally feeding. This happens too often now that I'm here actually writing a post about it. I get the messages about warnings for people who are verbally abusive, but what about people who legit go in 1v5's and purposely die? I'm aware how hard it is to prove, but if chat logs are saved and they're admitting right there they are feeding cause they don't care? I get too many of these games to hear that this system is working since if it was people would be scared to ruin the game for everyone else. I don't get to play much since I work a lot and this is just a terrible way to keep playing and quite honestly a huge waste of time whether we would have won or not since it just defeats the whole purpose of the game.