Why is There Flags All Over My Yard

[ncboiler]

I come home from work today to find neon spray paint and little flags all over my yard. Some say "Buried phone" and some say "Buried Electrical Cable" They trail from the front to the back of my house. There is also spray painted symbols in the street in front my my house. I pulled all the flags out of the ground and threw them in the garage. Why would they do this? Actually I have no idea who they is.

One theory; I don't have cable ran to my house. I moved into it when it was new and I have always had satellite. Is the cable company thinking I need it ran to my house? Maybe they have the wrong house?