Some people don't think alcohol and camping and fireworks mix well together. Some people don't want to be around drunken yahoos when they go camping in a public place (not that the OP was a "drunken yahoo.) The point is, if you don't like the no alcohol rule, DON'T GO THERE. There are many places that allow the public consumption of alcohol. That particular National Park was NOT one of them. BTW, that particular park allows alcohol at your individual campsite, but NOT in public areas.
The Park Ranger was trying to do his job, which was to protect EVERYONE'S "rights," not just the "right" of the individual who may or may not be vaping illegal plant material. If you don't like that law, you have the "right" to try and overturn it, through legal ways.
This wasn't the Wild West. Some individual "rights" have to be overruled in order to maintain the safety of the public. You have the "right" to drink in your own backyard, a party or a bar. You do NOT have the "right" to consume intoxicants in places where it is endangering/bothering/impinging upon other individuals. I DO consider myself a person with "balls." I DO know my civil rights, and I stand up against demagoguery, whether it be by the police or anybody else. I also know how to read posted rules. PS: I don't have kids, but I can understand how a parent or other individual could be concerned about someone "apparently" consuming illegal substances and/or alcohol in this PUBLIC place. There is a time and a place...This was neither.