Those clever little signs are cute, but I will never understand what gives somebody the right to kill another for walking where you shouldn't. Around here it's because they are engaged in making Meth or some other illegal activity. Years ago on a timber cruise in New Hampshire I was walking down a boundary line at the end of a long hot day. There was a house with the owners working outside so I put my dog on their leash, hailed them, then walked down and asked for permission to walk down their driveway. Based on comments here, apparently I'm lucky I didn't get shot for walking on their side of the line.