Not really. Even custom-built Game.exe and RGSS###.dll libraries get cracked. There is no such thing as safe software, just take a look at some torrent sites. This holds true for professional companies, so it is especially true for amateur game makers. I never personally heard of anybody "stealing" anything anyways, even if they did, it's not like they really gain anything from it, and you lose. Worse case scenario, and it is highly unlikely, someone takes credit for something you did.