Buying music through Bandcamp does not require a PayPal account. Once you click Checkout, look for the "Don't have a PayPal account?" link:
There's a small possibility that you'll instead see credit card fields after you click Checkout. If that's the case, be sure to click the "Review and Continue" button rather than the "Save your information with PayPal" link:
Don't see either of the above options? Unfortunately, PayPal does not allow credit cards in 100% of cases. Sometimes it's because of your location, and other times it's because of incorrect settings in the seller's account.