You can also get a Paypal Debit card and buy BTC or ETH using this card on a site like Coinbase.
It will take it from your paypal balance and should give you 1% cash back too.
Just keep in mind the daily limits are small though (Like 25 or 50 dollars a day for bitcoin purchases using a credit card).
Yea coinbase & CEX.io allow for this, as well as Circle.com! Thanks for adding that info.