Attention: Celebrities do not owe you anything.
They do not owe you an autograph. Or a photo. Purchasing a ticket to a show, or a concert does not entitle you to their time. They are not obligated to interact with you in any way. Therefore, if they do not offer to sign things, take pictures with fans, etc., you do not get to decide that you will bother them for these things.
This has been a PSA.










