It only makes sense that the White House consider new ideas that are supported by a large percentage of US citizens. It's not like the administration has a lot of free time to chase down every crack pot idea that comes its way. And, let's face it, it not that hard to get 5,000 nut-jobs to support a crazy, even harmful, idea (I bet someone could find 5,000 people to support the carpet-bombing of Washington DC).
The current total population of the US is just over 300,000,000. It only seems reasonable to require that 1/10th of 1% of them support an idea before the White House take time -- time that's funded by taxpayer money -- to seriously consider it.