Because US government is against cryptocurrencies. As long as Microsoft doesn't want to have problems with officials they won't take any risks. Especially risks like that: Bitcoin as a payment method is only for geeks and it's not worth keeping it just to satisfy them.
The US govt has made their stance clear.. so far.
For starters they enacted AML/KYC laws on exchanges. (which cover a wide range of issues)
Secondly they enacted Tax guidelines / laws.
Other than that as far as i am aware they have done nothing to hamper Bitcoin.
Hell, Marshall's even auctioned off Bitcoin before. (2013)
Because US government is against cryptocurrencies ?
Nope you are being dishonest and covering up the glaring issue.
BTC is failing at being a CURRENCY.. while you lie to make money of it being used as a commodity.
With out the one the other is useless..
Being dishonest is of no use.. it will not help your cause Bitcoin'ers.
BTC needs to be an effective and competitive currency alternative to other services already in use.
How can it be when it swings in price so drastically and so suddenly ?
And how can it be used when the fee's keep rising to ridiculous levels ?
You are being silly.
That is like saying customers don't want to buy a car that has no wheels and can't move.
While blaming it on the car color or something.