Maybe the correct question is Why is Breadwallet better than paypal.
Because:
Paypal is where your money goes. Money means $
Breadwallet is where your BTC goes.
So Paypa = Breadwallet, Dollar = BTC
except with paypal, you just have a promise for USD, and one that frequently gets broken, accounts seized, etc... with breadwallet you actually have real bitcoin right on your phone and also backed up on paper, not just a promise from some 3rd party service