For some breweries (many really) the pilot system is a 10 gallon homebrew system so clearly employees can drink that if they want or they can dump it. Generally they will plan on selling the first full batch.
Some breweries do pilot batches on their full sized system or maybe on an old smaller but still commercial sized system. They may serve this in the tasting room and solicit feedback, they may go through the trouble of making a label and registering with states so they can give it as an exclusive to a few drought accounts, they may dump it even. Of course some breweries (and almost all brewpubs) will just make a full sized batch of the new beer and plan on selling it to the public.
Talking to commercial brewers, they are less likely to need to dial in a recipe than homebrewers. They brew more often than us, usually with a smaller list of ingredients than us, and they just know far better how a beer will turn out on their system. John Maier has said he almost always gets what he wanted on the first try.