Interesting that I've tracked down the code enforcement group here in Clark County. They have said, repeatedly, and with much gusto, DON'T REMOVE THEM. Instead, take a picture and mail it or give them a call. They will note the location, and use the law to get the name/address of the person who posted them, and consequently, serve them with $100 fines for each sign they find.
They say they do this with great results, and have put a stop to much of it in many neighborhoods. A missing sign is nothing next to a missing sign and a knock on the door and cash out of your already failing business!
So, though I'd love to take them down, I'm instead making a nice little placard with the words "HerbaLife", "MLM" and "I AM LITTER" cut out of it. I'll place these over the signs, use my flourescent green $3 can of paint and hit the 10 or so I know about in my neighborhood.
#1. "RE: Code Enforcement says "Don't remove them!"" In response to Reply # 0
Excellent work. It's nice to know there is CE office in the region willing to do their jobs. And it's great that you're going to be out there helping them out.