I'm curious - what are these artificial barriers? In essentially the entire US (with a few very tiny exceptions), if you want to build out your own fiber and offer internet access, you can. You'll need to show financial viability (i.e. you have the resources to do the buildout), so the municipality doesn't end up with stuff strung on their poles rotting away, and half-dug trenches), but you can do it from a regulatory perspective.
The barrier is economic - it's a terrible business model. You're looking at $600 per home passed, at least, plus a couple hundred bucks (at least) to connect each customer. Plus your back-end (routing, backbone connectivity, etc. etc.). Then, you need to market, and convince people to leave their cable or Telco offering to sign up with you. Since they've often got triple play, you might need to consider offering video and phone service as well. Video programming costs are very high (particularly if you're small), and have fixed minimums.
Bottom line, pretty much anyone who's tried overbuilding has either (a) gone bankrupt (i.e. RCN), (b) have had a very large investment in place to protect (i.e. Verizon FiOS), or (c) not needed to actually make money doing it (i.e. Google).