More than the reward, the problem relies on spending hours on the same map, because someone has to go to their spawn - sometimes very far away - to kill the last bot (or hopefully make it move) - and it's not hard that that person dies after doing that, since the next wave spawns right in front of him.
It's just as if, in battle, one team had to run all the way to the other team's spawn, because they are camping spawn - but worse, because the bots just don't move at all.