We walked along the Prom and through town on Sunday afternoon and the whole area was heaving. I do see though that there are quite a few people who visit Llandudno that do not contribute much, if anything, to the town, as they bring their own food/drink and do not spend anything with the town's businesses.
You're getting the point now Dave, its weekends only, for a few hours.
Outside that 'sweet spot' many of the businesses are closing early, and in some cases opening later.
A case in point is Cafe Indugence. They open at 10am, but they know their first customers will be around 10.30 or 11am these days as most people have breakfast in the hotels or on the caravan site.
They close at 2.30pm, because they have learned that little or nothing their way after that time.
That's a very short working day is it not?
Imagine that happening in Blackpool say?
Your point about the increasing number of people who are coming who spend ZERO is also noted.