I change my own tires now, but I've watched many many tire changes at shops with tire machines and I don't recall ever seeing someone not use lube. Makes no sense not to use lube - less chance of gouging or friction-burning the tire bead (which will cause air leaks), bead seats much fast and with lower air pressure, less stress for the machinery, etc.
Having said that, I've never seen anyone use so much lube that it coats the tire treads enough to cause a slide out. Sidewalls and rims may get coated but lubes applied while the wheel is horizontal will all drip away from the tread and towards the rim.
I don't know if its mold release or some sort of preservative for rubber to prevent drying out while the tires are waiting to be sold, but I know there is something on them that makes them slippery when new... just put on a set of Anakees and got a bit of power slide going on the first corner in my neighborhood. Or maybe there's no contaminate on the tire, but the glass smooth rubber simply does not have the grip that the pock-marked (micro lands and grooves) scrubbed tire has.
Anyways, my normal ritual is about dozen tight parking lot circles, pushing the bike down while leaning the opposite way, followed by three passes (with progressively steeper lean angles) of the tightest twist road I know. I'm good to go in 5 miles.
Lateral G Junkie