That gag does not work where I am from. The legal age is 18 in England. I think I got asked my age in a pub once after the age of 14.

To get back OT, I had something odd happen to me in the British equivalent of Denny's. I walked into this place about 830 PM wearing a button shirt, tidy jeans and a short haircut, the real average guy look. There were very few people in there and the closing time was 11PM. Soooo, I stood by the desk waiting to be seated. I waited some more while two of the staff who brought food out from back looked straight at me then disappeared again. A manager looking lady appeared, looked at me, then went out back again. More food came out, and this time the girl carrying looked at me a bit puzzled....and vanished out back again.

I took a deep breath, counted to ten, then found myself a seat facing directly at the cooking area and the door the girls had been using. After a couple of minutes, one of them appeared, did a kind of double take, went back up to the front desk and brought me a menu. I thanked her and passed some comment about her manager not wanting the business. She mumbled something I missed and blushed somewhat. Another more cheery girl brought me my meal and when I was about 3/4 done the front desk was finally manned again by the manager looking lady. She was still there when I went to pay and leave. To my delight, they had a comment book in which I wrote something like "Waited 10 plus minutes to be seated in an almost empty restaurant. Are you trying to get closed down?". Mrs Manager took my money without looking me in the eye, and when I suggested she read the comment the look i got made it was clear she thought I was a puppy kicking child molester for having an opinion.

To this day I have no clue what the deal was in that place, be it a serious staff problem out back, somebody getting hurt or sick or maybe an equipment issue. Whatever, you do not just bugger off and leave the front of the place empty then ignore new arrivals. If you are having an issue, tell them that there may be a delay due to a problem out back. No need for details, but do not leave folk hanging.