I have no surprise that a LBS might shy away from this type of repair. First is that most LBSs are not too frame or alignment repair experienced, for quite a while the "repair" method of a miss aligned frame/fork was to seek warranty replacement. Second is that damage can be done if aligning is not carried out well. Third is that alignment is a very complex result of a few differing aspects INCLUDING the rider's body. (How do you align the rider's leg length difference that can cause a hip cant and thus side forces on the seat that are not symmetrical, as example). Fourth is to what standard does the shop align to. There are no such published ones that I know of. Fifth is that it's the result that counts and the only test (that I know of) of a well aligned bicycle (note I didn't say frame/fork) is the after aligning test ride. Now if the result isn't quite "good enough" (according to the rider's "feel") the bike gets broken down enough to do more aligning. This can be rather open ended as to time and thus cost. Few shops have the equipment to do controlled and safe aligning, and do so in a time effective manor.
Below are a couple of the many posts I have done here about alignment. It's worth reading through the whole threads as others have their points that are good. Andy
Front wheel turns hard right. - Bike Forums
Alignment thoughts - Bike Forums