It doesn't follow that just because a teacher wants the students to have fun it means s/he's a pushover.
It depends on the teacher's motive. If there are games just to kill time or because the teacher already gave up on teaching the students then s/he's a pushover and lazy.
Games could complement lessons. If the students are learning while having fun then no one would complain. If they actually like what they are doing there is a greater chance that they would actually retain the target grammar or sentence.
