Freebies: The nation’s largest theater chains are giving away promotional samples of candy, popcorn and other goodies to regain revenue lost by cuts in on-screen advertising. United Artists, the largest movie chain with 2,500 screens, handed out PB Max candy bars this month to patrons entering its theaters in Los Angeles. Cineplex Odeon, the second largest chain with 1,690 screens, handed out packs of sugar-free Dentyne chewing gum and samples of Hero’s men’s cologne at the end of the movies. One industry source estimates the nationwide distribution of a free product can generate up to $100,000 in ad revenues each month. Instead of paying for ads on screen, which audiences have rejected, companies pay a fee to the theater chains to hand out their products.