I never understood the x amount of times you can launch the demo. At least not in the other games where the games are only parts of the full game. Is the SSB demo any different? A limited amount of how many times you can launch it would make sense if they give you the full game and limit you to few times, but giving you a demo with few features and still limiting it to few launches... Oh well.
More on topic, probably good that they made the early demo only limited to fewer people. They can fix most bugs found before releasing the demo to a wider audience which would probably allow them to fix even more bugs if they are found before launching the game.