It's not clear to me from that USA Today article... what the cable lobbies spending that money on? Advertising aimed at residents? What do those ads look like? Or is it just "lobbying" (bribing) the local officials?
In Fort Collins, 2b was a ballot measure. Most of the money went to advertising. I had a hard time finding direct examples online, but this article (http://www.coloradoan.com/story/news/2017/11/01/fact-check-f...) does have a picture of the many mailers received by some voters. (I lived in Longmont when the second vote happened and can confirm many similar mailings as the article)
I live in Fort Collins and can confirm that we were absolutely inundated with mailers, and other forms of ads.
Advertising is definitely a big part of it. A common angle is to release commercials basically saying, "we shouldn't be spending government money on fiber when we could use that money for [insert emotionally-charged need that could be improved in literally every town in existence]"
Eventually those companies will have to start lobbying for those alternative public investments - the emotional argument is far more effective when <emotionally-charged need> is on the same ballot.
Money being spent on advertising is a bit of a dubious figure coming from an advertising company. If Comcast is putting local ads on their cable channels saying "vote no", then quoting the retail price of those ad spots is going to inflate the figure. Sure they may be giving up some potential revenue, but the actual cost to the company is not what is quoted.
I wonder if they get to claim a tax deduction for “donating” air time in this manner ...?
They would be donating it to themselves, so I hope not. One could maybe imagine a situation where they setup a super pac and have that organization spend the money on political advertising, but that seems so easy of a dodge that the IRS must have a way to detect it.