Any celebrity who thinks they are a celebrity is one too many, in my humble opinion.
They may be famous, but that makes them no more special than my/your Gran. A thankfully small number come under the heading "Don't you know who I am, give me a free upgrade/etc"
Many years ago I met Roger Whitaker (a Radio 2 crooner of the day) - he was at the peak of his success, and delightfull. I was 18 and more into the Stranglers - but he was happy to sign autographs for the ladies serving in the Stansted canteen (it was an old Nissen Hut, seriously).