Payment processors are the answer my mate.
You can also work with 'approved' addresses or something like that where a merchant trusts an address that has succesfully been used before.
It has been discussed over the years. Indeed what you state is the next step service providers can monopolies on.
However as Litecoin is another network that is used for payment at merchants and with the advent of scrypt asics that network will show more promise for fast stable transactions.
Bitcoin transactions are extremely fast, if you consider the slow banking system. The litecoin network may be faster, but it doesn't have such a large user base.