I don't know what the rules for a franchise are, but the good dealers will give you a take off is the owner didn't want it. They do throw away a lot of stuff. How many calls can you get for a stock exhaust system?
The local dealer does sell merchandise on EBay, but it seems to be markdowns and discontinued stuff that he actually bought. I have not noticed any take offs.
When I had the 95" kit installed, it meant a pair of leftover cylinders and pistons with only 1000 miles on them, when I asked for them back, they looked at me real surprised and why sure you can have them, lemme see where they went. I'm sure they considered them throw-away. The bored out parts were only about $650, and I'm sure they'd installed a hundred of the kits, so leftover stock parts would be plentiful.
So now, if I ever need to take another 88 to 95, or a 96 to 103, I'll just have to buy pistons and have these cylinders bored out to match.