It's always been a marketing gimmick....nothing less, nothing more.
That has not changed, and will not change.
There is no such a thing as a "deal". Sure you might save a little bit but at the end of the day the company and retailer still make their profit.
There is no magic
It hasn't "always been" a marketing gimmic. There were legitmate deals to be had, but it wasn't like it was an everyday thing. I'm talking 5+ years ago before Amazon prime shipping and all of the deal sites (groupon and the like) started popping up.
Woot had some great prices on things that were a) tax free and $5 shipping whether you bought 1 or 20 of them. At the time Amazon had limited options on free shipping and Prime wasn't in play to make shipping even more attractive. Things that were normally $30-$40 on Amazon were on Woot for occassion for $15 + $5 shipping. They had things like headphones, iPad cases, misc electronics that made good stocking stuffers and gifts for people that you could buy 2 or 3 of and save a good chunk of money.
They used to offer deals on those huge DLP TV's for like $500 less than you could buy locally (or on Amazon) and have them shipped for $5. If you were in the market for that kind of thing it was good deal.
For me the turning point was once they moved from a single item and went to all of the other .home/.wine/.shirt/.don'tcare categories and changed the site into what all of the deal sites look like.