I won't give a long and drawn out answer to the question. Suffice it to say that TFL is a closely moderated forum and as such we will close/edit/delete wherever and whenever we see that the threads or posts require it.
We might close threads more frequently than those other forums you frequent because we try to stay ahead of the bickering that is inherent in almost any topic you can mention. In other words we are proactive instead of reactive.
If the subject of a thread is off topic for TFL or is "stupid" as you put it, we will close it on sight. We've found that such threads don't die a natural death, but some, otherwise good, members who participate in them will die an unnatural death by banishment. We honestly try to avoid that, and if closing a thread prematurely, by your reckoning, is the cost, then so be it.