I don't get charged each time I use my debit card.
You are mistaken.
Yes, you do get charged each time you use your debit card. You just aren't aware of it, because it's hidden from you. The merchant is paying a much larger fee that bitcoin transactions cost, and the merchant is passing this cost on to you by increasing the price of his products or services.
This is, IMO the best feature of bitcoin. It makes the cost of a transaction much more transparent to the consumer. I am not surprised that the OP thinks it is free to use a debit card (as I assume that most people believe this) because merchants generally will not sell items on different terms to people paying with a debit/credit card (except maybe have a, say $5 minimum purchase, or ask to check ID).
or process a payment by Debit/Credit card. No confirmations needed.
You are mistaken.
The merchant does not have a guarantee that they will get paid when you use your debit/credit card. A debit/credit card transaction is similar to an UNCONFIMRED bitcoin transaction. Generally the merchant won't receive the actual money in their bank account for many hours. Even then if there is a dispute, the money can be taken back from them. Bitcoin transactions take seconds to propagate through the network and reach a point where they carry less risk than a debit/credit card transaction. Typically within 10 minutes the transaction becomes permanently irreversible, and spendable by the merchant if they choose to do so. If the merchant wishes for less risk and faster conversion into fiat cash, they can use services such as BitPay or Coinbase that take on some of that risk and add convenience for a very small fee.
Even if the merchant were to receive cash from a customer and verify (somehow) with 100% certainty that the bills are not fake, the same would be true. The merchant would have the possibility of having cash stolen from them and would have to eat those losses. Until a merchants money is taken by armored truck to the bank and their account credited, even a cash transaction is "unconfirmed"
My money is accepted around the world at almost each and every merchant
You are mistaken.
I tried to spend my US dollars at many merchants in Ireland, and not a single one was willing to accept it.
I would have to disagree with you on this one. The US dollar is almost universally accepted throughout the world. Even if the USD is not the local currency, it's value is known around the world and there are few places that will not accept dollars.
I then tried to spend my Euro at many merchants back home in the U.S. and not a single one was willing to accept that either. Bitcoin is quickly gaining popularity and acceptance. There are already many merchants that accept it quickly and easily:
This is true.