I'm surprised they didn't pay you on top of that since you'll be surprised how valuable that information is to them, it's like gold.I rode Buells all day as part of a test group once. We got a t-shirt, backpack and lunch. =)
I'd have paid them to have as much fun, though!
I helped unload Moto Guzzi Nevada 750s from a truck once for a demo event. One of the factory guys offered to let me take one up the road briefly. Later that night, I was sitting around a campfire when moto-journalist Brian Catterson showed up. After our introductions, I asked him what he was up to and he said they'd come to try out the new 750s the next day. "They ride pretty nice", I said. He looked at me funny, "You've ridden one already??"That's pretty much it lol. It seems like a privilege opposed to a "job" to do for them.
The incentives like OpenRoad said are the t-shirt, backpack, and the lunch. Oh and getting to ride a bike before the vast majority of the public does.