i do wave at anyone with mower and trailer, its pretty easy around here to figure out who's doing it legit and who's doing for cash after work, or they got laid off and started cutting lawns to make money, while they collect unemployment. there's a lot hacks around, that will even signs on their trailers, but then their trimmer looks like its from the early 90's has no guard on it, and has duct tape for a grip and the 8" cone they have is tipped over on its side, its kinda comical. but i still give them the wave, or you can tell which guy just got into it, because he has a brand new truck, all his equipment is either homeowner quality or 20 year old commercial stuff, that looks rough. the guys that have been in it for a while, already know, that a shiny new truck, won't help make the lawn look better, or help them spread more mulch or really do anything better. they all know its the operator and equipment. the ones that are doing it legit wave back, the ones doing it illegally or that are jealous of my setup because i work hard, are the low ballers and they don't like to wave back.
fully lic. and ins. 10yrs exp.