I don't see anyone talking hate. I just see people wanting others to competently execute the very job they are hired to do.
Complain to their managers. Of course, that's not necessary now, because they marked the garbage cans and the employees know now what needs to be done. It was really the boss taking "the easy way out" and avoiding the issue. Not sure why, perhaps he realistically thinks that we can't solve the problem anyway, so just make it obvious for them.
I would have made a simple phone call: "Your employees are skipping our location every day. Please have them come by and pick up our trash."
There's no point in "expecting" anyone to do anything if you are not their boss or their customer. If you are a customer of the business itself, then complain to management.
Expectation, frustration, anger, contempt, disdain, hatred. One leads to the other, none of them are healthy, none are productive.