He was paid by the company to interject with quips during the demos, so any rudeness is understood by both parties. An awkward situation for all involved.
He was paid to be rude to the people who were paying him to be rude? That might not make it not rude, but I can't imagine anything that would come closer.
It was rude to be rude to the people paying him to be rude because it appears to the other members of the audience who were not being paid to be rude that being rude and interrupting the talk is acceptable practice.
