Well said iCEBREAKER.
This buy wall is really insane why is there a wall at least as big as the natural bid volumes
No one can know for sure, but I would guess its either to tempt big holders who want out to sell to them at decent discount, or to prop up trading above the wall so that they can exit their existing position at higher price.
Those reasons are probably the most likely.
Also since there is no confirm button when you trade on poloniex, an accident where you market buy or sell could potentially happen. To minimize the risk many will place either a buy order or sell order far away from current market price. I do this myself, in fact more than 100 BTC of that wall is mine. But I also placed my bid exactly on that price for fun. Which brings us another reason. Sometimes people place a big wall for lulz. It's fun to see people's reaction to crazy things.
I haven't been on Polo in many months and it boggles the mind this is still the case.
BTW Einstein had something to say about ether. I bookmarked it a while ago before I heard of ETH, never read it because I forgot about it.