I get the Heimer support that dances in lane and Feeds

I really don't understand why every game I get in, the matchmaking feels the need to pair me with the people who will play vayne top go 0/8, or the heimer or leblanc or olaf support that choose to troll. NEVER does this happen on the enemy team, always on my team. Things like this make it so frustratingly hard to win it is unbelieveable. Dynamic queue makes this feel almost a 100X more often and I don't know why. I thought people would pick their roles and champs since they get to choose between 2 now. Yet some people still feel the need to troll, /endrant.