This is a multi-edged sword in my opinion. On the one hand as a seller I'm trying to make the transaction as secure and convenient as possible for the buyer and myself by using Paypal (I've never had issues with it, knock on wood) but at the same time I'm not willing to necessarily take the 3% hit on the price of the item to do so. So I don't feel at all bad asking the buyer to pay the fee, it's just the cost of doing business. And I no longer advertise anything as including Paypal fees, I just say "any applicable transaction fees". I don't think they could get me for that. As a buyer I have no issue with someone asking me to pay the fee or asking me to pay in bank-funds so that they can accept the Paypal payment without having to have a Premier account.
To me it's like if I was asking $100 shipped for an item and someone offered to come pick it up, I'm certainly going to adjust the price to reflect the fact that I don't have to ship it. So if someone wants to suggest a method of payment other than Paypal I'll adjust the price accordingly.
I don't think the gas station analogy applies to the type of transactions we do here as I'm sure for large businesses it is a matter of whether or not a customer would use your service if you didn't allow for the use of a CC (or whatever).
Finally, for what it's worth the formula for figuring the total payment required to net the asking price = (price + $.30)/.971 - at least that's what works for my premier account.
Nate