If I had to guess, I think the low number of Emrakul decks is probably a combination of there being more straightforward colorless commanders available, Emrakul having a nasty reputation for demolishing one players game when shes cast, and her pricetag staying at or above $30 for years
But demand also means more retailers are ordering from distributors, including stores like Hobbycraft and The Entertainer that didn't used to sell Pokmon cards
Haze Frog and his much more reasonably-costed Spore Frog are also key players in this deck
It is not as good a threat although it does offer some reach but given that it is also half the price, is playable in many more archetypes and is also a mana ramper and fixer The drawbacks of this card as life gain are that it is slow to get life returns from it, it will situationally not work for life when no dead guys are there to be exiled, it is reasonably easy to kill and it cannot give you a big single injection of life
Fetchlands are also a really good way to get a shuffle when you dont like whats on top of your library
There are also platform fees + shipping to consider
