You are correct, just like anything, it has its pros and cons. It, however, has been my experience that dentists that switch to medicade are not necessarily "bad" dentists, but the time constraints placed on them by the demanding patient loads tends to lower the quality of work.
I know a dentist in south Florida that started medicade and it was my impression that he was getting burnt out after a year or two and you and I both know that if you have a successful office grossing say right at a million a year, it would be down right insane to switch to a medicade program.
As for the service aspect you are totally right, but there are many other ways to serve those in need of dental care other than medicade.
-C