Yep I agree.
I think they smell so bad for 2 reasons:
1) Can you really be bothered to worry about not missing when it's not your own house?
2) As you say since most of these places have become drug dens most "normal, hygenic" people do not use them - so its bound to smell bad.
I haven't used a council run public toilet in years, as you say they are terrible compared to those run by supermarkets or other businesses (e.g. motorway services).
