Some things seem like good ideas and some just don’t. This falls under the “don’t” category.
I’ve told my wife, “If I ever buy meat from a door to door salesman, please just shoot me on the spot”.
http://www.komotv.com/stories/44951.htm
Update: Many folks have pointed out that there are some quality, ethical meat salesmen that sell meat door to door. I actually have some friends of mine that are very happy with the meat they recently got from a meat salesman that came by in a MARKED, refrigerated truck. So, I think this falls under the same rules as just about everything else. DO YOUR HOMEWORK.