You know what? Maybe I'll start shopping at HSN instead of Amazon, because as we all know, HSN's higher margins obviously means that they're a superior store than Amazon's crappy margins. </sarcasm>
Red herring. If HSN and Amazon are selling the same crap, prices correlate more directly to value. Otherwise, if an apple costs 50 cents and an orange costs 25 cents, which one do you want?
Profit margins are irrelevant to the discussion.