Ebay encourages buyers and sellers to use paypal. Ebay has a conflict of interest in regard to promoting paypal as a payment method due to ebay owning paypal. Everytime paypal is used, ebay profits from each paypal transaction by way of charging paypal fees to sellers.

Whether you pay by credit card through paypal or you pay a seller who is a registered business with a credit card and the seller/business processes the credit card payment because they have a merchant credit facility, you automatically have some form of protection whether you use a credit card through paypal or you use a credit card not through paypal.

• For a seller to be able to process credit card payments, they have to be a registered business and they are accountable for the transactions they process.

•  If a buyer complains to their credit card company about an  unauthorized or fraudulent credit card transaction(s), the seller/business will be investigated by the provider (regulated financial institution, a bank or credit union) who supplies the seller/business with their merchant credit facility.

•  If the transaction(s) was fraudulently processed or unauthorized charges were made, the buyer will be refunded. If your credit card is charged and it turns out the seller is wrongfully charging your card or there are unauthorized charges on your card, if you report it to your credit card company, there will be an investigation and if your card was fradulently charged you will be refunded.
  

• The only way a dishonest seller/scammer can get away with processing fraudulent and/or unauthorised charges or charge and send out no goods is if the buyers do not report the wrong doings to their credit card company.

Paying for purchases using a credit card automatically gives buyers some form of protection. If a seller is a registered business and they have a merchant credit facility, they can process credit card payments. Those sellers may not be interested in using paypal as paypal is expensive in regard to fees, those sellers are already paying fees/charges to have a merchant credit facility which a bank or credit union provides them with to enable them to process credit card payments, there really is no reason for those sellers to also accept credit card payments via paypal when they can process credit card payments themselves, a service they are already paying for.