Because you can make a comparison to other events does not mean it's the same thing. Also the rewards from Garrison are better than all the events you mentioned combined. I mentioned it because I think it's an easy adjustment to mention some guidelines for Garrison-taking which would improve the experience for newer players drastically.
Also people who are new to the server but not new to Rust are very familiar with bradley, helis, and rigs. They have no idea what the garrison is and they never will if certain people take it down within 5 minutes of spawning each time.