There's another element of force involved. The government forces Joe to offer a service, smoke-free dining. Why not force him to offer exercise classes at the end of every meal, too? Because the majority of patrons don't want it? I guess that means that smoking bans have nothing to do with rights or objective criteria of public health, just majority whim. By that logic smoking restaurants were fine until the moment the opinion polls tipped against smoking.
Exactly.
And when the government forced Joe to offer the service, they took away Bob's target market, because bob's Place was already smoke-free.