Some people like to play games at the cottage, on the train, while crossing the Pacific on a 12 hour flight to Incheon, etc. There are reasons why people don't like having to constantly be online. Ubisoft had the big debacle with their servers going down, saves being lost, and other such things. Flight sims can sometimes take hours without time acceleration, and inflight-saves are not that common. I don't want to spend an hour or two flying to a destination, shooting down a personal best, and having my game crash to the menu and lose all my progress a minute before landing because my wireless router hiccupped or the net connection blinked.

I'm not saying that companies shouldn't try and protect their product, but if they went with a "have to be connected to play" DRM scheme then what's to stop players from getting screwed over if the company's decides they don't want to pay for the authentication server after a year because sales have slowed? People are still playing the game, but they're not giving the company any more money. Maybe the company might not even release a patch to allow offline play before they can the servers? Maybe they don't have a choice because they went out of business or got bought out and it's out of their hands.

Lots of stuff can happen, and sometimes being a physical copy Luddite pays off.