Tagging- stupid kids!!!

The only bad news of the day, someone tagged our retaining wall We live on a hill and have a rather large retaining wall, we've been here 16 yrs. and have never had anything like this happen before-UGH Luckily we have left over paint from when we painted a year ago. so I went out there and painted it as soon as I noticed it! DH and DS thought I should of had the cops come out just in case it was gang related- I think it was just some kids being stupid, so I didn't think about it! I just wanted it gone! I guess if it happens again I'll call, crap why do they do things like this!!!