It'd take them 5 minutes a day to shut down all the infringing sellers on e-bay, so get over yourself, moran.
Calm down, there's no need for insults.
Firstly, you only checked English speaking eBay. You'll find lots more pirated roms in various forms on eBay. Also, informing eBay once doesn't stop them from popping up agian. It would be a very difficult thing to police, I mean, checking eBay for new stuff would be some guy's full time job.
Then that's just a MINORITY of the pirated nintendo game sales. With lots of stuff retail in so many different countries. The sheer FAST ammount of copyright lawsuits necessary would be massive, meaning signfigant legal fees for court cases that likely wouldn't break even. It'd be a money it. The best Nintendo can do is target the larger causes and hope it 'sends a message'.
It's estimated that bootlegged materials make up 5%-7% of the total global industrial production. That is a huuuuuuuge ammount.