Yea, it's unfortunate that we have to deal with criminals on a daily basis. I've been consistent in my advice here, never put anything on Thingiverse or similar if you think it has mass appeal. You'll lose it forever. At worst, put it on Quirky.com or something and at least you'll have a fighting chance to maybe get it produced for sale.

Don't get me wrong, I do like "open-source" development and sharing ideas. It's a great and noble philosophy. But, there is nothing wrong with making some money on a good idea. "Open-source" works well for software but I don't think it's a model that is suited to hardware. I realize that without open-source hardware, RepRap would not exist. It certainly provided a foundation for RepRap printers to explode on the market, but, for accessories and clever upgrades, I have no problem with people making some cash.

Bottom line, protect your ideas, don't just give them away and always get a Non-Disclosure signed if you share the idea (that is, any idea that you don't wish to just give away) with anyone.