This is not true. As the venom is not collected under sterile conditions, it is of no use to any medical facility in the production of antivenin. This beneficent claim by the roundup organizers and supporters is a patent lie. Rattlers are nasty vicious animals just waiting to attack. This, too, is untrue.
Most bites happen because someone has put their hand or foot somewhere without first looking.
Hikers and rock climbers stick their hand into a crevice trying to find a handhold. Campers go walking around with their eyes on the distant vista rather than watching where they are going. Rather than defusing an encounter with a startled rattler by stopping all motion and slowly walking backwards out of strike range, many victims attempt to find rocks and sticks to throw at the snake, flailing their arms, stamping their feet, yelling and jumping around, all guaranteed to strike fear into the heart of, and elicit a strike response from, any snake. There are species which are already protected under state and federal wildlife laws and several others which are currently being evaluated for such protection. Rattlesnake bites are rarely fatal.