Working on the assumption that "they'll never find out" doesn't magically make it legal.
And sticking a copyright notice on something doesn't automatically mean you can't use it.
Fair use. Look it up.
Crowd sounds are in no way a significant or integral part of their copyrighted work, therefore sampling them would likely be as legal as taking quotation from a book.
Of course they could still sue you since nothing in the legal system is as black and white as we would like it to be, but you have about the same chance of being sued for that as you do for someone becoming addicted to your game and suing you because they quit their job because of it. And you're not gonna stop making games because of the miniscule chance that some idiot might sue you for that, are you? So why give up your fair use rights because some corporation decided to stick a copyright notice on their TV program?
Now there's a good idea. Better quality than recording from a TV and you're in no danger for copyright infringement.
I'm pretty sure you'd likely be in far more legal danger of being sued, or even arrested, for bringing a recording device into a stadium than you would if you simply sampled it off the TV program. Sampling crowd sounds off a tv program is likely fair use, and legal.
And even if it is not legal, it would almost certainly be only a civil trial, where they would have to prove damages, which would be minimal at best. Ie, at worst you'd face a fine.
Bringing a recording device into a stadium on the other hand... If it falls under the same pervue as movies do, then that could well carry the penalty of jailtime! Which of course is absurd, but who ever said the legal system was sane?