What beekeepers are you referring to, specifically? My wife is a beekeeper and I can tell you she keeps chemical-free as do most in these parts. Beekeepers are very sensitive to issues of chemical contamination, especially with the rise of CCD.
No offense meant, I certainly wasn't referring to you, or anyone specific.
My generalization is valid on the whole, and all the more so with any commercial operation, which, let's face it, accounts for an increasing amount of the bees being kept these days.
I applaud your wife's direction and it's one that I and others are also taking.
There are many many others who think nothing of introducing pesticides, miticides, fungicides, and essential oils, all of which, as you've said, can have devastating effects both short term and long.
This is all separate from the issue of what the bees encounter when they forage, too.