Thing is lots of people obviously want discount codes so all a code site is doing is supplying them and providing the experience the user wants. The better sites also are unique content, with retailer articles, offer descriptions, community and all the rest. Okay we have the reveal code only to find there isn't one gripe but that can happen for any valid reason also. Not nearly as irritating as all those run of network ebay/ask.com ads you see clogging up the listings.
Plus leave your codes out in the open and they all get scraped so really I don't see the beef, its a decent enough biz model, perhaps the challenge is for the better sites to try and distinguish themselves from the mass but competition is healthy, it feeds innovation.
The users obviously find them useful, thats what google wants, the merchants want more sales and its not like these sites are forced on you, a user has to seek them out. So really I can't see these sites bothering all but the tiniest minorities of people.
Move on, accept, grow old, get fat, far better things to whinge about methinks
