TV shows don't last forever.

The people they buy from understand that Mike and Frank need to make a profit.

I like the show - my favorite on TV since it aired.
Not of all time, but it's the best on TV right now.
No yelling, fighting, drama, sex, bleeps every two seconds, no controversy, just two down-to-earth genuinely nice guys who have been real friends for many years who work together.
They treat the people they meet with genuine respect and kindness and they get it in return - plus they and the viewer, at least those who love the show, are entertained by their dry sense of humor and those they meet.
It's a refreshing show to not have to worry about being offended and just simply be entertained by a couple of nice guys who are in our living rooms every week who could easily pass as our own friends if they were there watching it with us.