eBay...
It allows folks to sell on ebay and receive money quickly without having to set up a credit card system.And even with the credit card system it can take several days to actually get your money.
Paypal payments are available as soon as you customer hits the payment button.
Further The majority of folks on Ebay take Paypal and many ONLY take Paypal.
Another nice bit is a Paypal Debit Card gets you a 1% Cash Back on just about every purchase you make. (people who have the older Debit accounts like me get 1.5% Cashback)
So Paypal does have its positive side but they are a bear to deal with if you run afoul of any of their policies.
Paypal has its good side, but like many webcentered businesses they're a pushover for whatever political activists that have the upper hand. They should be a bit careful, though - they are used by quite a few folks that might earn them more than just a bit of lost business.
Here's a couple of the less harmful examples. There's a gazillion like them and worse. One of these guys had some fifteen minutes of internet fame as "The Skunk".
Ebay only LETS sellers accept PayPal (which ebay owns) or "ProPay."
The last time I sold a piece of antique amateur radio equipment on ebay, I listed in the ad that I accepted PayPal or Postal Money Orders only. Ebay pulled my ad saying all transactions had to be through PayPal or "ProPay."
At that point I re-listed the equipment with "PayPal only" and it sold quickly.
Then, PayPal notified me that my transaction was "suspicious" and notified me it was holding MY MONEY until the buyer of the equipment "approved" the transaction and acknowledged they received what they paid for.
I got on the phone with PayPal and argued my way up their "management chain" and after several hours had MY MONEY released that night, which I promptly transferred to my bank account.
The buyer "approved" the transaction several days later telling PayPal the item was "better than described."
At the time ebay and PayPal pulled this crap on me, I had a 100% user rating and more than 100 successful transactions as a seller. After this experience, both eBay and PayPal can kiss my ass. I stopped doing business with them, period. I no longer have a credit card or bank account linked to them, and I've removed all my personal information from both ebay and paypal.