No, you do not have to use PayPal. To purchase downloadable tracks you can now either use the Major Credit Card option, which uses the Braintree Payment Gateway, or the PayPal option to pay for them. Even if you do not have a PayPal account, the payment screen you are taken to in PayPal will allow you to use any major credit card.
Both options use proven, secure method for online payment and provides PCI DSS compliant processing for your credit card. That's geek speak for "they protect your number, man"!