I've heard of opposition to those signs for businesses and public areas, with an argument that carrying a gun in public is a civil right. I've never heard of any serious opposition for forcing guns on personal property, like homes. I'm sure some wingnuts are out there on the ultra-libertarian fringe, but I've yet to meet one in real life.

For my part I see the signs as useful. If I see a "gun free" sign on a business that just tells me to spend my money elsewhere if possible.