Bibbity - you have said (amongst other things)
MNHQ....pretending not to notice that aibu is just awful?
Why can't mnhq moderate just a tiny bit so that the threads in the topic actually make sense?
But having such a disproportionate number of threads in aibu simply makes Mumsnet and Mumsnetters look a little bit silly, I fear.
I don't much like the shouty nature of it either and the very odd "well you posted in aibu so what did you expect?" line that gets trotted out regularly
To me, that's not the same as what Maryz is saying
putting everything in aibu defeats the purpose of having topics - because apart from a few specialist topics and the quichey threads (and by that I include all the long-running threads, the anti and post natal, the support threads etc), posting any thread anywhere other than aibu is very unlikely to get any replies at all
The attitude on aibu is of secondary importance, imo
Then your comment:
I have suggested to mnhq that they simply scrap all topics and rename the site AmIBeingUnreasonable - they don't want to seem to do that either
... is just naughty 
Maryz I don't think the car seat one does prove your point, I think it proves mine
Topics are OK within reason, but don't provide a good space for general discussion/debate.
FWIW - I don't only use AIBU. I use 'Threads I'm On' and 'Active'. Some people hide or choose topics and unless you are buying a car seat I can see it being one that would be hidden, however, the thread would have been of general interest.