If the network participants obtain an utility there is value. One example that I commented several times here in HN: I live in Buenos Aires, Argentina, and when foreign customers paid us via a wire transfer the inefficient big banks (that exist almost everywhere) calculate an exchange rate that is not very fair. Doing the same transfer by Bitcoin and converting it (100% legally) to our local currency gives us a better rate which means more profits for our company. Other examples exist but at the core what is happening is that there are financial innovations that the regulatory framework is killing and can be leveraged with these technologies. Sure, there are a lot of scammers right there but this is another topic.