The price bracket of those two processors is completely different. While X79 board have no competitions, 220W boards to AMD FX must compete against 150W Z87 boards. You are throwing high capacity components in a board aimed at the mainstream market.
I know the extreme edition Intel processors are a different price bracket than mainstream Z87 .
What I saying is that I dont think all AMD FX processors require 220W boards.
AMD FX processors which run at 4.6+Ghz require high end motherboards.
OCed 8320, 8350 & 9000 series.
Heck there are people on Overclock.net running 4.8GHz on the 99FX Pro R2.
Going 4.6+ Ghz on FX series demands an atleast decent quality board.
Plus the most expensive AMD board Crosshair V Formula is 220$.
One of the most popular Haswell mainstream board the Asus Z87 Pro costs 185$ right now.
35$ more is not that bad considering AMD doesn't change sockets every year.
Although AM3+ is EOL right now.
You get 4.8 ~ 5Ghz on Asus Sabertooth board and it costs the same as Z87 Pro and dont want to shell money for halo boards.
It is a myth that you require a 200$ board for FX.
To summarize, as I told you before that mainstream Intel processors when OCed could draw close to 200W and most regular Intel MOBOs handle that. If the manufacturers can use these kinds of components on Intel MOBOs than they can do it for AMD aswell.