I absolutely do see what you mean, especially about speaking with other children.
At the same time, I realise that if I limited my child's exposure to French to "perfect" situations, she wouldn't learn French at all. In my case this is particularly key as you may know from other threads that I am not a native speaker myself but am trying to bring my daughter up bilingual. If she didn't have that constant stream of "pretty good" input from me, she'd have no chance when the occasions to be with "perfect" speakers came up - it just wouldn't work.
I realise, of course, your situation is different, but I suppose what I mean is that one has to take every single opportunity and keep the end goal in sight - being too choosy can defeat you in the long term.
Something I do do is that, as much as possible, when my daughter is with me, it is 100% French - by which I mean that, not only do I speak to her only in French, but if the TV's on it's in French (DVD or TV5), if there's music it is in French (CDs or radio Nostalgie on the web - my daughter is still too small to be cool), if I read to her it's a French book (if she brings me an English book I will either translate it or, more often, stall and then help her pick a French one); all her toys have French names, even if they're different from the English ones (Bruce the Bunny becomes Laurent le Lapin) ... and so forth. It may sound hard but for us it's just like that. True, it may get harder as time goes on - after all, it's hard to pretend that Claude Francois is "in" these days ...