It's definately sickening sometimes. What it ends up boiling down to is what is the alternative? PayPal has the market saturated just like eBay does - how can anyone set up another payment service that so many people already have accounts with?
If I shut off my PayPal shopping cart on my website, nobody would buy anything. I don't ever have customers contacting me saying 'hey, I don't use PayPal, can I send you a check?'.