The problem lies with the immediate damage that GP32 warez are doing to the GP32 and it's software NOW.
The GP32 is a small platform - thus requires as much in the way of sales as possible even to keep it afloat.
Most of the emus available f0or the GP32 are for systems that are no longer being commercially made, or the games being commercially sold. Therefore, the damage being done to companies even if people decide to copy the roms they dont own, is minimal - it's more a technical point of law in that case - about intellectual property. Look at it like this - Anyone who DOES do this is technically doing no damage to a company that is massive anyway. I am of course not justifying it, just making a comparison here...
Entware/Liksang etc are currently doing a good job of supporting the GP32 by providing the software for such a niche market. Using GP32 warez puts this in immediate danger, and all for a few pounds/bucks/won etc that you may have to pay out. In other words, you are doing IMMEDIATE damage to a small company that needs all the support it can muster.
THAT is sad.
Yes - I have seen GP32 warez. NO - I have never used them out of principle of damaging such a fledgleling company and killing it off forever.
You asked what the difference was? THAT is the difference.
Cheers