The thing is that with net metering, solar power users are effectively using the grid as a giant battery that they charge up during the day and discharge during the night.
They aren't paying for use of that battery, but the utility company is still expected to maintain it. If you're not buying electricity from them, then they are providing that service for no pay - and that's not a sustainable business model.
It's not a problem when only a microscopic percentage of users have net-metered solar power - but if a large number of people do it, then there could be a huge problem...and if there is ever more daytime solar power being generated (eg on cloudy days in winter) than is being consumed - then there will be a GIGANTIC problem to resolve - and that's going to require massive investments that they won't have.
So I do have *some* sympathy for them. They should, at some point, be allowed to charge for the service of effectively storing your power for you...although we're not remotely close to that point right now.