Heck no. People should be allowed to eat as much as they want. It's unfair discrimination which is based purely on prejudice and nanny state crap.
Also, where would the line be drawn? Could restauranteurs turn away people who are fat and actually healthy, etc, whilst people who are skinny and actually really unhealthy due to their diet are allowed to come in?
That, and their profits would drop by 40% at least. Bad news for the economy, just like any size-discriminatory laws, thankfully.
