I know people are going to be crazy about that number, but I'm not sure the money altogether matters.
It counts exactly the same against the salary cap whether it's $800,000 or $20 million a year. If money isn't an issue for the club (and knowing Manchester will be spending 100 million+ pounds on transfer fees *alone* in this window, it's not), then they're not concerned by one player making $8 million per year.
With the salary cap being so low, you're still looking at this club spending around $23 million to $28 million per year in wages. That's a ton for an MLS club, but again - Manchester will be spending more than four times that just to bring in players to further compete in England. This is wages on a free transfer.
If it were me, I'd rather see that $23 million spread across the full team. MLS doesn't allow the club to do that. So instead, we get a bunch of big-time marketing signings, while guys like Iraola - big time guys who are actually under the DP threshold and will help to swing games - are more of a rarity than Pirlo or Kaka signings.
But, overall, the money's not really of concern to me, and I can't imagine that it's too much of a concern to the club, either.