Incidentally, California state law allows people to collect signatures and get their message out (as long as they don't disturb the peace) in any public place,

Incidentally, California state law allows people to collect signatures and get their message out (as long as they don't disturb the peace) in any public place, and includes grocery stores in "public place." I remember seeing people collecting signatures at the mall when I was a teenager. The mall always posted a professionally printed sign saying, essentially, "these people have a right to do this, but we don't agree with them and we ask you to ignore them."