I have no problems with critters in beer. I just think that random critters can have potential dangers. My reading about lambics has more than once mentioned the so-called "enteric" phase of fermentation has potential hazards associated with it, does not produce desirable flavors or characteristics, and that the commerical producers try to avoid these forms of microbes (despite the "spontaneous" nature of lambic fermenation. It is for this reason that the commerical yeast banks do not include the "enteric" bacteria in their blends, and authors like Sparrow advise us to avoid these. I agree that a finished lambic will not harbor living enteric bacteria, even if they were present in early fermentation, but lacking the capability to figure out whether the beer has anything harmful in it, I choose to avoid random bugs.