At best youll deprive them of a few key resources, at worst (and more often than not), youll make their deck more consistent by trimming the fat
Sure, there are players who don't own any cards (or don't care about the few cards they do happen to own), prefers to proxy up the decks they play, and couldn't care less about the flavor, editions or conditions of cards they use
Yes, usually Myr RetrieverMyr Retriever wins out against its older compatriot due to the lower mana cost, but crucially, AzlaskAzlask's WUBRG ability doesn't provide trample or any other evasion like most OverrunOverrun effects do
Many of the strongest green spells are widely printed and accessible
Some of my favorite memories from college were dorm drafts where one of us would walk to our local game store, buy a box of the latest set, and wed all gather that night to draft
Traditional foil and halo foil ghostfire cards are available only in Tarkir: Dragonstorm Collector Boosters