Tried hiring a local goat rental to tame my parents' yard, the guy on the phone complained about "this thing called a living wage" that he has to pay his workers. He won't take jobs less than 10 acres or his business runs at a loss. Many cities need regular plant clearing, though, so by reliably selling services to local city and county governments, his business will never fail.
And cities are starting to do this more regularly too. E.g. NYC's Riverside park was cleared with goats this year. (https://www.reuters.com/world/us/goats-released-new-york-cit...)