Do API Credentials Do Anything?

Hi WCFM Support,

I recently downloaded your direct PayPal pay plugin and I was testing it and came across something. As a vendor I added a PayPal account that does not have any API credentials (personal account, not business), then I entered random numbers into the API fields and saved it. I then used another account to purchase a product from the vendor to see what would happen. The payment was successful and went to the PayPal account email the vendor provided, and the email the vendor received even said that the sale was eligible for seller protection: https://snipboard.io/IHPf0B.jpg . So I was wondering if someone could tell me what the API credentials actually do? Because it seems the transaction went through fine without them.

Thank you for your time, Anthany

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