Its different because it shouldn't actually be required to have a connection that you always have to play for, month after month, just to play a game. Hell some people have really nasty bandwidth caps and every little byte counts towards it and don't want a game taking it up.
Because they could easily do something slightly different and allow offline play which would not allow for trade of weapons and stuff, along with online play where they could trade stuff.
Its easy enough to do. On gets saved and loaded to the local computer, the other only gets saved and loaded from the secure server.
The game experience they want to give people would still be the same for people who are playing the single player, except for the fact that they could not sell their stuff, but if they were not going to do that anyway then there is no difference in game experience.
Some people don't have constant connections, either because they can't get one, or because their connection keeps dropping and can't switch to a better provider.
Requiring people to have a constant connection also stops people from playing while they are going to work, or traveling. You're sitting in a bus/car/plane/train/boat for a number of hours and want to play your game that you legally bought, but can't because even the single player requires a constant connection. You want to sit in the park for lunch and play for 20 or 30 minutes, but can't because there is no wireless. Or you are traveling for business and the hotel you are in doesn't have internet.
And the biggest reason why people are pissed at them, is because its a game company telling them when and where they can or can't play their legally bought game.
Imagine you needed an internet connection to use note pad? Or to watch a movie on your computer or dvd/blu-ray player? Or to browse your files on your computer? How would that make you feel? I bet you wouldn't care till you were working on something, and then your net connection goes offline for 10 seconds to a minute and you've lost everything you were working on. Or your connection started dropping every 5 to 10 minutes for what ever reason.
Again, they could do the smart thing and easily include a way to play offline without compromising the online stuff. Its not that hard to do and they would sell far more games.
Just make it knock that when you start a character, that they can either start it for offline play where they would not be able to trade anything but doesn't require a connection or can start one for online play which would allow trade, but would also require a constant connection.
And allow them to have both so that if they want to do a little online stuff they can jump on, but if they are don't then they don't have to.
Again the reason why people are pissed is because the game company is trying to tell them when and where they can play the game they legally bought.
