That is inconsitent with the assertion that a ban is not harmful to business. I thought you were saying that any "drifting off" of smokers is likely to be more than offset by increases in attendance by folks (smokers and non smokers alike) who prefer the non-smoking environment.
Oops, I mistated your earlier assertion. It was ..."there might be some lost business but the amount lost would be more than offset by increased profit margins."
Sorry about that, you didn't say increased attendance, you said increased profit margins. That implies not going out of business, eh?
Increased profit margin implis less work for more profit. A business's only purpose is to make a profit not increase sales.