Writing from the perspective of international travel since the late 50s, 3 years in Europe with the Navy, steady business travel since 1965 (most of it admittedly in the US), a Hell of a lot of resturant dining over the years, and nearly five years as the restaurant critic for a newspaper of modest circulation out in the sticks, my response would have been simple (unless already placated by a servile manager craving pardon)....

1. Finish dinner.

2. Take check, hold it in the air, and announce to all and sundry that Hell would freeze over and several squads of police would be required for me to pay it after having a tray of drinks poured over me. In case all don't hear the first cries, cry more loudly the second time.

3. Pull a "Joe Welsh" (the Boston Lawyer who bearded Joe McCarthy): "Have you no shame, you paltry poltroon (in other words, make a big scene, for after all, the staff and manager will be there tomorrow and I won't)"

4. Get up and walk out with a stony glare, in essence daring the swinish innkeeper from attempting to detain me for a civil debt (which the last time I looked in the US, or most states therof, not subject to jail time.

Illigetimi non carborundum! After all, you're the customer.