Proliferate can be helpful for all the same reasons it can be dangerous
If the binder is mostly staying inside, or not holding very valuable cards, you probably wont have much need for a zipper, but if the binder will be frequently bouncing around a backpack, or holds more valuable pieces of your collection, a zipper may be in order.
No Pokemon TCG trainer looking to make their mark on the world would be caught without at least a few of these powerhouse cards
Moving counters with Innkeeper's Talent, Terrasymbiosis, or Branching Evolution can add counters faster than vendors give out swag at MagicCon
Many MTG Commander staples use delayed triggers to generate massive value over multiple turns
He's yet to be unseated as top dog, and any new planeswalker that did so would probably be courting a mass ban like the one Oko received