are they selling gold? Selling real estate?
This is a purely bitcoin operation. The value for end users is being able to receive bitcoin quickly/instantly. The value for you is to earn transaction fees.
We do not handle your money either. When you sign up, you enter your PayPal address. We quickly check that your PayPal account supports the payment methods that are needed. Then, the money in dollars is paid directly to your PayPal account by people, who receive bitcoin from you. The process is completely transparent.
Your money does not go through us. We do not even have access to your PayPal account. People pay to you directly.