I get paid through PayPal and see that there are no charges for receiving money or transferring it to my bank. I use a corporate account. Plus, what really surprises me, is the exchange rate is as good as a charter bank gives. No complaints obviously. Now when I sell something on eBay I get dinged a service charge to receive money. This is a personal account. Is this the same for you people who get paid into a personal account from micros? ie no charges.
Don't forget that PapPal started life as a completely separate company to eBay (although eBay later bought them out). The 'service charge' is simply how they make their money for providing the facility to pay on-line. Nowadays that service charge (paid only by the seller) is also paying for the insurance in the event your goods don't arrive and the seller disappears.
I'd also agree that PayPal's exchange rates are competitive with standard bank commercial rates. In my experience they are a much better company than they usually get credit for.
There's always a cost when providing a service although for a long time many of these charges have been 'absorbed' by the retailer. With the competitive nature of the internet many retailers are now listing these charges, notably credit-card charges, separately.