There's a tendency for overeaters to ruminate on what they eat in private. But when observed by an objective third party, we can see they actually eat more in public:

http://www.webmd.com/diet/news/20120203/people-pleasers-may-overeat-at-parties

Shame or social pressure only feeds this tendency.

I hope this doesn't sound flip, but think of Satan's plan for our salvation. We humans NEED the freedom to make mistakes. We need to face the consequences of these mistakes, knowing we made them of our own free will. Growth requires free agency.