I don't think even the service levels from online retailers are that bad. I ordered a set of lights from
Wiggle, one of which arrived faulty. Got a rtm note from the website, mailed it back, got the replacement and a refund of postage by return.
In fact I only returned the faulty rear from a set and got a whole new set back, so i have two front lights, one rear, and two sets of mountings for the price of the original set. Expensive Cateye ones too. Dunno if that was just a mistake by them or a genuine gesture, but a result either way.