This thread is silly. People are complaining because they're venting their anger at Ubisoft and the actual DRM itself. It's adding an extra and hefty barrier to purchasing a game that is in demand. Think of it this way, when the PS3 was released it was in high demand but the price point annoyed people as they couldn't afford it. People complained that something that was in demand was unreasonably priced. Sony suffered then; Ubisoft will now.
As for the DRM itself it's a single player game, and when you're immersed in a fantasy you don't want to suddenly be taken away from that immersion due to something that's out fo your control (think of the annoyance of a game crashing, now add the extra connection loss scenario). Many people will want to play on the go or on a system that may be offline for certain periods. Or, they could have a large family that share a connection. The number of potentially game stopping scenarios are endless. It also doesn't help that EA and Valve have implmented online services that actually work, where you don't need to be connected to the net all the time.
The people complaining are the people that want the game but refuse to purchase the game because of the DRM. It doesn't help that the pirated version will be superior to the retail copy so potential legal customers get shat on from a great height.
edit- Just like to add that when people complain (preferably directly to the publisher in question) then that publisher are more likely to take notice. It's fine to just protest with your wallet by not paying for something, but unless you tell them why you're not purchasing they're game they may not know what exactly they've done wrong and pull all support. I personally don't see it happening but that's partly because I'm pretty sure a lot of people will have directly vented at Ubisoft. I know enough people did with EA at the install limit thing so they've changed they're DRM system. It's not perfect, but it is better.
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