I'm a CompBio PhD student, and my experience is that folks in that field are much more careful with statistics than in, say, molecular biology labs, but it varies from lab to lab. My PI is exceedingly meticulous about stats -- for instance, we don't report p-values, but rather entire distributions -- but that's because our work is all in silico, so it's easy to run tons of replicate simulations. Wet lab work that's finicky should definitely be held to high statistical standards, but I don't think it's fair to presume everyone in the field guilty until proven innocent.
But wet lab scientists should be even more careful! They have way less control over the system they're trying to study than you do, so stats are the only security net we have to even attempt to do anything with the data we produce.
I also agree on the innocent until proven guilty part, but by now I've seen and talked to hundreds of people with the best intentions, who do not realise how important careful examination of the data is, so I'm growing a bit disillusioned.
I think it is entirely fair to presume biologists incompetent and sloppy until they have proven otherwise.
(My impression from admittedly limited contact with biology students and from browsing through the occasional paper is that most of them barely approach mediocrity from below.)
