for example you buy a cup of coffee using BTC, you must wait until 10-15 minutes
maybe we must pay at first and wait that bitcoin payment confirmed while we drink coffee

No, payment is done immediately and the shop receives it immediately, you don't have to wait at all.
as said before by others - the only question is a trust to this transaction, for which you need to wait for any confirmations.
But as it is something not that simple to make a double spend - nobody would try to do this for a cup of coffee.
This is similar like creating a fake credit card to go to pay for you coffee, definitely this is possible today, but nobody does it.
Same with Bitcoin.