EDH started as a community driven format with no official support. The community decided that your deck must be exactly 100 cards with no duplicates except basic land. This slows the came down and forces more board interaction.
On top of that 1 of your hundred cards must be a Legendary creature. Everything in your deck can be of a color from that creature and you will always have access to that creature throughout the game. This constrains deck construction and makes it really hard to splash a color for one $50 that would be perfect. Always having access to commander is a comfort to new players and opens new strategies to veterans.
To further combat this I have a pool of 30 or decks that I build with my friends and we play mostly from this pool. No paying to win if we are paying together.