i use paypal all the time i think to pay someone all you need is the email, whoever is collecting i believe has to sign up so we the payees can send $$$ and they can collect.
this is what their site says:
What you can do with your PayPal Account.
Send money to anyone with an email address. Login and click the Send Money tab.
How to send money
1. Sign up for a PayPal account, if you don't have one.
2. If you want to send money from your bank account, get Verified.
3. Log in to your PayPal account.
4. Click the Send Money tab.
5. Enter your recipient's email address and the amount.
6. Review your transaction, then send it.
How to request money
1. Log in to your PayPal account.
2. Click the Request Money tab.
3. Enter your recipient's email address and the amount you're requesting.
4. Your recipient gets an email and instructions on how to pay you using PayPal.
How to receive money
1. Receive an email from PayPal saying you've gotten a payment.
2. Sign up for a PayPal account or just log in to see the money added to your PayPal balance.
3. You can transfer the funds to a checking account, request a check, or send the funds to someone else.
4. Or just log in to see the money added to your PayPal account balance