My product was not a competitive threat. It operated within their ecosystem and was only used to help people give them money faster. A lot of people were pretty confused when they decided to shut it down.
The project's operation depended on accessing factual information published on the F100's web site (things like event times, maintenance status, etc). Since this is data that originates with the F100, there is no reasonable alternative source. Someone else in the community started abusing this data in a way that led to bad press and the F100 unleashed their $1k/hr law firm on everyone they could find that was reading data off their site.
We were sent a cease and desist alleging infringement of the CFAA and copyright/trademark infringement for accessing their web site in a manner disallowed by their Terms of Use (which state the site cannot be accessed by any spider, crawler, bot, or any other automated or manual method). We were able to pay for a few hours with a lawyer who had experience in the CFAA and he tried to get them to agree to a licensing deal, but they refused to do so. Since I could afford to buy 4 hours of his time, the EFF (of which I have been a supporting member off and on for the last 10+ years) decided I didn't need their charity and lost interest since I had shown "ability" to pay for my own attorney.
Barring the materialization of $1 mil+ that I can send to my lawyer, this is where the matter lies.
To be frankly honest, I can understand how, from the perspective of the F100, it's easier if my side project simply doesn't exist. The problem is that their company shouldn't have the right to decide that. We aren't supposed to allow companies to decide who gets to exist.
For example, car companies can't say "Oh, you know, I really don't like 7-Eleven putting gas in our cars, I'm going to send them a C&D telling them to stop." If 7-Eleven is capable of providing a functional gas pump, it is the consumer's choice whether or not they wish to input gas there or at a competitor, and the big car companies have no say in the matter. The same should be true in the digital world, but it's not.