My fault for posting in haste and not dobule checking. The bit about restauraunts was retracted. But not, as far as I know, the law against selling refills still stands.

My attention was drawn to this law by a refill shop which as far as I (and they!) know, are not still not allowed to refill a container. Here's a UK legal guidance page:

e.g. https://www.gov.uk/guidance/olive-oil-regulations-and-inspec...