They often aren't. I was in a shop a few months ago where a patron was asking a counter rep about hunting laws and specific scenarios. That's what lawyers are for.
Different shops have different ideas about the laws as written and as they and/or their counsel perceives them. To some degree you can "answer shop" if a certain shop won't do what you'd like. Granted, of course, that it's something that they are at legal exposure for (like MA compliance) not something that is straight illegal (postban high caps, true AWs, etc.).
Different shops will transfer different things as is their prerogative.
ETA: There are some great (as in, terrifying) stories of things gun shop employees have said.
My two stories
1.) An employee of a well-respected MA shop told me Glock told them that they will no longer allow FFLs to ship them firearms for repairs. This was the same day Glock's rep told me to use an FFL to ship it. I had a different FFL do it without any problem.
2.) My personal favorite: I was discussing M1 Garands and an employee piped in, "you gotta be careful, when they were converting M1's from full auto, they made a lot of mistakes and cut some corners."