But 1 premise; that BYO causes a loss in restaurant profitability. I'd argue the opposite; BYO offered by a restaurant increases profitabilty even ignoring the corkage fee. It causes more business and more profit on other foods and drinks; when I have a good wine that I enjoy, more food, fun and frolic follows.

As for tipping, why not tip based on the corkage? Is that any different than the charges for rent, heat, electricity, etc. that every restaurant has built in to their menu prices? If you don't tip on corkage, then you need to work out the labour component of your food and tip by the hour