^ Currently coinbase complies with KYC/AML, and is backed by some pretty big names in the financial market. They're still relatively new for a large company, but they seem pretty stable and reliable already.
There are no big companies that accept bitcoin that does NOT use a btc payment processor. They simply don't have the infrastructure to do it themselves, because processing crypto currency is nothing like Visa/Mastercard.
This is also because most big companies do not really have any way to pay their bills in bitcoin.
Expedia may accept bitcoin but United airlines, or American airlines do not, the Hilton does not, Hertz does not. As more companies accept bitcoin more large companies will be able to accept bitcoin and use that same bitcoin to pay their other suppliers.