i wish you could...our society doesn't allow it. parents get to say and do nearly whatever they want...you make it sound so easy.
It's actually quite easy. You just have to be the adult in the room.
As an example, my daughter plays travel softball. In the last year we've gone to Huntington Beach, Colorado, Pennsylvania, Chattanooga, Atlanta, Crown Point, Peoria, St. Louis, Kansas City, etc. for nationals, qualifiers, and exposure tournaments. (Patrick freaking Murphy watched one of her games earlier this fall!!)
Organizations set the standard for how parents will behave. If they set expectations properly, the relationship exists between players and coaches. Parents are there to cheer for the girls only. Well, and drop them off/pick them up (before they can drive themselves).
Organizations that don't set expectations stand out like a sore thumb. Parents are wandering in and out of dugout, coaches are on edge, it's a charlie foxtrot. And I can guarantee that those coaches are receiving emails/texts from those parents left and right, ******** about playing time and God knows what else.
I've seen both. I'm quite happy to be part of one of the good orgs.