Also Rodot has given away the circuit schematic for free which anyone can use (and indeed has used) to breadboard a Gamebuino or design a PCB of their own. He hasn't been compensated for the 1+ year work he's put into the project nor will he be once the Indigogo campaign is over. What he did achieve by keeping the PCB layout proprietary is ensure that enough people subscribed to the campaign rather than elsewhere, which was needed in order for economies-of-scale to kick in to make the whole thing viable in the first place. So no, it's not quite the same when you think about it.
There's nothing to stop anyone from selling games independently, assuming they can make something good enough to attract a market, but from my experience in the game industry I think it would be very difficult to set up a store. First of all you can rule China out (and many others), even Google Play haven't been able to get around the logistical nightmare of that one. Second, every country in the world has its own consumer rights which must be honored, particularly in cases where trade agreements exist between the consumers country and the sellers. Someone's going to have to handle refunds and spammers and keep an eye out for fraud and all the other fun stuff that goes with online shops, and then there are the tax reporting issues...it's bad enough when you're the only one doing the selling let alone trying to set up a store for others to sell as well! Now think about all that headache and hassle and cost involved in setting up an operation like that and ask yourself if it's really going to be worth it given that we already know the exact size of the entire Gamebuino marketplace: 487 people as of this morning.
Or we could just have an awesome forum where people get to swap tips and and ideas and source code and maybe compiled hex files and if people want to figure out a way to sell their game on their own they can do it in whatever way works best for them