It will eventually get to a sad point where this ceases to be news, but today is not that point. Homefront is the latest game confirmed to be using THQ's online pass system, which restricts the online capabilities of a pre-owned game unless the customer pays the publisher for a code.
That is not to say that code-less gamers can't get online at all. All maps will be available, but you'll be restricted to a punishing level cap of five, compared to the 75 that brand new buyers can achieve. If a pre-owned purchaser would like to get to level six and beyond, he'll need to stump up an additional $10.
I still think that devaluing pre-owned games in this way is damaging to the industry overall. If it ever gets to a point where trade-in prices are significantly diminished because of it, gamers will lose the ability to make much trade-in credit, thus making it less easy for them to buy brand new games. Publishers have a blinkered way of looking at the market and they can't see how this might bite them in the ass.
At $60 a game (and with GameStop claiming that trade-in credit often goes to new games), methinks you'd want to encourage customers to make any saving they can and be better equipped to buy your wares. Apparently I'm wrong, though.