The LBS where I purchased my bike does not charge me for installing accessories or parts that I buy from them. However, I would never even dream of expecting something like that for a part that I purchased from somewhere else. I believe they charge for even small services if you did not buy the bike from them.
They also give free lifetime tune-ups for bikes that they sold to you.
I think that this is wonderful, but even if they did not give this free service, I would be willing to pay. I like to support small local businesses as much as I am able.
-Sue
Burning fat, building fitness . . . one mile at a time . . . one hill at a time.