of course, not even just Paypal, maybe many others will also use bitcoin as a means of payment.
That is correct, many will most likely use bitcoin as mode of payment because it is more convenient and easy to use. I can also use it to pay for the services rendered if someone will agree with that payment conditions.
This thing will be true if you want to payment to another country, because the transaction fees of Bitcoin is worse than the transaction fees of FIAT and Paypal if you paying for national bills. But, I like to using altcoins for my global payment than Bitcoin, because there are have some altcoins can provide a services transfer money with cheapest fees and faster than Bitcoin.