Micropayments aren't an inherently bad idea. They work for funding services, which is the purpose they were originally intended for. AWS's pricing is pretty much micropayments, though they only bill at certain thresholds to avoid the problem with transaction costs. They don't work well for funding content, and even if they did I don't think Hubski is large enough, but there are circumstances where they work.
There's a big difference between B2B "micropayments" where you're buying into a plan that you expect to cost a stone crapton of money and capital-M Micropayments where you, the end user, are meting out currency a fraction of a cent at a time. On the one hand, you know you're in for several thousand "micropayments" that will comprise a real-money bill. On the other hand, the end user is contemplating spending $.0015 sending an email and trying to decide if it's worth spending $.0030 more to cc two people. The former works. The latter doesn't.