This doesn't look like a "buyer charge", just a notice from PayPal that your credit card company may charge you (independently), most likely because you are making a payment in non-USD funds?Having said that, PayPal definitely tries to steer people away from paying with credit cards and instead paying directly through them. If you are sure it's a USD transaction then I'd brush it off as a "marketing" tactic.--The DIN Rail Mount kit for Arduino: quickly attach your Arduino to standard DIN rail
In fact paypal was playing its tactics to direct me to transfer cash to them with my bank. I made the credit card payment and I didn't see additional charge on my card. The amount requested was in USD anyway, as the seller reminded me. Just look at their chart, 80 pixels for $142 and 66 pixels for $138. That ought to represent the actual 3% difference really well! Plus their lame color scheme trying to make you stay away from gray buttons. Shame on paypal.
3.12 Debit Card Processing. PayPal will process your debit card funded transactions through either the ATM debit network or the Visa/MasterCard network. If we process your debit card through an ATM debit network, we may provide you with the opportunity to switch to a Visa or MasterCard network by clicking the "Funding Sources" link on the payment review page. If you use your PayPal Debit Card for a payment that is not in U.S. Dollars, your transaction will be funded with your U.S. Dollar Balance, even if you have a Balance in another currency. Any required currency conversion will be performed by Visa, MasterCard, or a similar third party and may be subject to a fee by that third party.
Maybe you did read my last reply but the currency is USD, which is what I use too. Paypal always uses grey color for credit card payment button and have you go through 2-3 steps to do that. That has been for at least a decade.
I was mostly OK as a buyer except for this time but as a seller I curse paypal for charging a lot for transactions. They milk small businesses hard.