Anybody who puts a ps3 game on a torrent site is playing a really dirty trick on you. You can be sued, but if you're determined to download one, you'll find after you finally get all 20gb or more of the game downloaded at 10 kilobytes/second, which will take about a day or two, you will still need a blu-ray burner to create disc; finding a blu-ray with enough space is difficult and expensive; and when you finally burn it to a blu-ray, and put it in your ps3, the best that will happen is the ps3 will deem it a BD-R containing "unsupported data." The worst that will happen is the firmware update may have code that will scan a BD-R for copies of games and instantly ban your ps3 from PSN for life. There is no way to escape a PSN ban because your ps3 has unique hardware signatures, MAC address among other things that only Sony knows about.You'd have to download an older firmware, reinstall it and then never log into PSN again.
There is no way to play copied games in ps3, especially not disc games, and no iso loaders either. If anyone does one of those things, it would be like the dude in 1984 painting "I hate Big Brother" on a big sign and hanging it in front of his 2-way telescreen. Sony runs your ps3. They are Big Brother. You may own the ps3, but they still own the operating system. You agreed that your right to use the firmware includes not using mods or hacks, when you hit x on the "yes" option after downloading it. You also agreed that Sony can ban your ps3 for a EULA beef.
I bet somebody does have ps3 games up on torrents just to be a jerk, cause they think it's funny to waste people's time.