In all seriousness, I don't think the store did anything wrong. He probably just made it clear that your big peep, string and limb silencers WERE slowing your bow down - which is true. Obviously, you're gonna get a little more noise and vibration now that they're 86'ed. You should have known that. Don't shoot the messenger.

Truth be known, if you're good at what you do, that extra noise won't be a factor. People have been killing big deer with loud bows for a long time. A deer isn't going to dodge your arrow inside 25 yards unless he's already busted or winded you, no matter how loud your bow is.