there are so many boosters because there are sooooo many boost buyers.
more than half classic players doesn’t even want to play the game, they just want to buy their way to max level and then buy boe/consume/gear…etc and this is why there is millions of gold being sold on classic and for that the game is filled with bots.
in 2019 classic (that was the reason blizzard started to sell shop boost and tokens and the game was filled with tons of gdkp) now it’s not much different, people are still buying boost from mage’s and buying gold to buy w/e they can just to obtain what they want! it feels like no one play for the game play itself anymore and maybe this is why classic is not a place for anyone who want to play for nostalgia or fun.