That is only your assertation, minion. I have seen no numbers anywhere to corroborate this.
It is simply not arguable that the costs for running two separate seating arrangments, the slower turnover of tables from smokers and the extra cost for equipment and supplies increases costs.
It is arguable that the effect on revenues is an unknown variable which may be different from one location to another. In that respect a ban on smoking area wide provides insulation from lost revenues.
As far as facts and figures, the best evidence is that the large chains are banning smoking. They have the ultimate responsibility to maximize profits and gain market share. If there actions lowered profits and/or market share the market would be creating smoking establishments FASTER than nonsmoking ones. In that this isn't the case, the numbers speak for themselves.