I'm all for them - they fill gaps left by schooling! Our social history is very poorly taught - largely because it is not (from what I can discover) on the curriculum - or if it is, then it is only there in so far as it affects 'history' in a larger context, so if you don't happen to have been studying that part of our history you will not hear about them. Then you go for a walk in the park and some across a statue to someone with a brief note about what (s)he is being commemorated for and you think Ah,... interesting - now how does that fit in? and go away and look them up...