Currently caffeine is a free-for all. Highly addictive.
Where do you get this? How do you define "highly addictive"? Are you reading stories of people sucking dick for caffeine?
Teachers, and most adults, I find, do not have the same mindset, or level of energy: typically, if it means doing anything more than standing around, talking with other adults, they don't want to do it. Just count the number of adults who actively engage the kids in games on the playground outside of school hours. If you find just one, I'd be surprised. And I don't mean a parent pushing a kid on the swings; that takes almost no energy. By extension, I think if teachers see kids getting a little too active, it threatens their comfort level because the teachers may actually have to do something other than stand around.
Car analogy: My speedometer goes to 150 mph, so I should be ticketed because I possibly can go that fast, even if I never do?
But guess why we don't have mandatory draft anymore? Because Boomers said, "Not my child!" and threatened any politician that dared suggest it. And who created the Millennials? That's right: Boomer parents. And they're narcissistic little shits because their Boomer parents hovered over them, coddling them, treating them as if they're "special" and God's gift to humanity - because, for God's sake, a Boomer created the precious little thing - preventing them from learning how hard life really could be, leading to spoiled, entitled kids. So if you want to bitch about how crappy the younger generations are, Boomers get the blame for that, too.