VBulletin abuse of power?

Anthony Boyd writes: "A representative for the VBulletin software product has revoked the license from a site simply because he found the material objectionable. He initally claimed it was due to violation of law until people started quoting the law to him. Then he said they revoked the license because it violated some "morality" clause in the VBulletin license — but people looking at it are unable to find such a clause. What do you think? Was this capricious or reasonable? Is it justified in law? As a VBulletin customer, how secure do you feel about your license?"