This is a very unfair forum topic. How can you judge someone based purely on one incredibly brief meeting? We all have days when we'd tell even our most loved family or friends to sod off, so you can't expect celebrities to not feel the same.
Many of these stories lack any context. You don't know whether the chap who Tom Baker alledgedly told to f**k off was incredibly annoying and harassing him.
Let's not be so swift to judge people so quickly. Enjoy what they give us in the films and TV shows they appear in and stop expecting people to be a far better human being than you are 24/7
Whilst what you say is true, the public are, in effect, the customers of celebrities.
People who work in the service industry also have their off days and come across people they find annoying, but it would not be acceptable/appropriate for them to show customers a bad attitude.