If they do it to every customer they can convince? It will make a difference.
I think it comes down to what kind of equipment you have. If it's a 10-11 speed rear cassette, then maybe the chain is a little worn. If it's 5-6 speeds, no way. If it's 7-8-9, probably not. But regardless, MAKE the LBS show you OBJECTIVE evdence of chain wear; don't take their word for it.
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I stop for people / whose right of way I honor / but not for no one.

Originally Posted by
bragi
"However, it's never a good idea to overgeneralize."