Have you looked into why this is happening? Maybe it is due to attempting to recoup investment in current infrastructure built when the technology was more expensive.
In many cases, no. They made that back years, even decades ago.
The municipality is on the hook for the bonds.
Correct. Which is why I said 'mostly'. However the bond money allows a multiplicative effect, once formed the cooperative is able to use said funding to secure more funding. For that matter, the bond is at least a known accounted for risk.
I did mention that my preferred form of utility is indeed a cooperative, didn't I? As for the 'advantages', I'm going to point out that they're advantages shared by for-profit companies that the government is trying to lure into the area. For example, Tesla goes to build a battery factory, various governments line up to offer them various incentives - free land, tax rebates, services, and such if they'll only build the factory in THEIR jurisdiction.
Do you see how those and other advantages make competition by private companies difficult if not impossible?
Why do we have to make competition by private companies 'easy'? Why do we have to 'guarantee' a private company's profits, especially when they're doing a lousy job?
Like I've said before: people don't go to the hassle and expense of setting up a cooperative when they're satisfied with their internet service. They only do so when the available ISPs are horrible.
Even in your example of the NG coop there is no competition as the current supplier has a monopoly in the current service area.
The current supplier isn't a cooperative and doesn't want to expand. They ended up going with a cooperative type system because NO commercial company wanted it.
Private companies have to save money from profits to expand and upgrade systems. In this model all the coop has to do is go back and float another bond. It is pretty easy to do when it is coached like "Support this bond or your internet access will fail".
I have to ask - what do you have against cooperatives? As for floating another bond, well, if it's looking to expand, it has to convince the CURRENT customers that expansion is in their interests. Which can be difficult. 'Floating another bond' would only work if they were expanding into a DIFFERENT bond area, basically a different local government paying them to expand into their area. Keep in mind that in such a system the customers are also the owners. I occasionally get a check from my power company because of this, and I get to vote for the board members.
I've had the best experiences with cooperative utilities, the worst from commercial for profit ones. In NO cases was the government still continuing to fund the cooperative, it's only in the startup that they get funding, and that's generally limited with the starting company having to borrow money on the basis of it's assets and business model in order to finish construction.
Besides -
Private companies have to save money from profits to expand and upgrade systems.
No, actually they don't. There are many options, which includes borrowing money to gain the capital to expand. Secured loans for property, same with a family buying a home.