That works out to about 21,000 lbs of rodents allowed to live and breed over the course of a year - if you ever needed evidence that people are really really stupid, here you have it.
I kill every damn one of them I see. My first bite put me in the hospital for 3 weeks and then it took 5 months of physical therapy before I could walk without crutches and about a year before I walked without a limp. My buddies grandson was hit in the foot, they had to amputate his big toe. A coworker got hit in the hand and they had to amputate his little finger and ring finger. Rattler bites do an incredible amount of tissue damage and nearly always leave permanent disability in some manner. They are a big problem out here in West TX and a big threat to any who work in the oilfields so pardon me if I do not share your sympathy’s.
As far as the rodents go I don’t have a clue where you came up with that number and don’t really care, but to suggest that a 5 lb rattler eats 50 lbs of rodents a year is laughable. A rattler on average eats about 4 to 6 times a year We have more than enough critters around here that feed on rodents, bullsnakes, coachwhips, skunks, ringtails, possums, raccoons, fox, cyotes and bobcats and I didn’t even mention about 20 different species of raptors. We can survive just fine without rattlers.
If that were the case, we'd be up to our ass in rats since the roundup has been going on since 1958.
It's to help the ranchers protect their livestock. You might want to keep better control of that broad, 'stupid' brush until you know what you're talking about.