Should the mechanic ever return in the future, Roses price could soar
Making it immune to destruction effects would make this thing a vastly better wall, since few decks will be able to get a monster over 7000ATK, and as such they'll most likely have to use some form of non-destruction removal (Compulsory, Castel, etc.) to get rid of it
Sometimes this means the actions of the non-seeker investigators arent as efficient, they may just be taking an action to engage an enemy for instance
Over there, you can put out two "Slime Monster Tokens" without a time lag, and from the next turn onwards, there is no Special Summon limit
Heres an Overgrowth theme deck opening
The scene at Costco here is reminiscent of last year's Stanley Cup craze , when people fought for the drinking cups at a Target Starbucks location