>From what I could tell the business model seemed to be 1) send entirely generic form letter at very little cost to dispute every single ticket, regardless of merit 2) assume that you can overwhelm the system and they'll just give up on some percentage of the tickets 3) profit.

But isn't that (claimed to be) the exact model used by the parking authority? Write tickets without a lot of care for getting it right, knowing that most people aren't going to fight it? What's good for the goose...