Because, when you send the money using the CC to someone, the request will go into the bank, after that this should get confirmed by the banks and government or other organization and then they will send the money to the destination. Of curse, all the banks, organizations, governments will not work for free. They take some money as transaction fee, sometimes directly and sometime not directly. We call banks, government, etc... as third part object, this how a centralized systems looks like because in any transaction the third can control or monitor your transaction.
But of curse, due to the banking network system speed (they usually use internal networks and call it intranet) people will think the transaction are very fast.
Most people wont care about any of this that you wrote. I am not saying that they shouldn't care, but that is just how it is. Credit card transactions have fees, but so does Bitcoin. From the perspective of a user who wants to send/receive money from Point A to Point B, he won't care where the fees go to. Whether or not a central entity or a decentralized one takes his fees, wont matter to most people. They will only care how much it will cost them and how convenient and fast the service is. A $100 international CC transaction will always have the same fees. With Bitcoin, those fees will depend on the address types, inputs/outputs, used sat/vbyte fee range. A $100 bitcoin transaction can cost $0.06 one time, $0.20 the other time, and $10 the third time. When the average spender sees this, especially those with not so deep pockets, he won't care about privacy and third parties.
But still, if you want your transaction to be instant you can put enough transaction fee and make it instantly done.
Faster confirmations require more fees = more expensive transactions.
