More on the "painted" lawn

I passed by the lawn I mentioned earlier this week and now have something of an answer. The lawn is n ow completely and utterly dead. There is also a sign near the front door advertising the work being done.

Ah, it appears that the green "paint" was actually a dye or something else used to mark the application of an herbicide to insure that they covered the entire area. It makes sense now that I have a few other clues to lead the way.