I own a traffic exchange in addition to my gambling site. I know lots of exchanges that had their accounts closed. Most for the following reasons:
1) paid auto surfs allowed
2) received funds from a paid auto surf or HYPI in the past
3) received gambling funds in the present or past
Because of the above, many of the popular exchanges don’t accept PayPal – even if you have an affilate program, make sure it is one level only.
I accept PayPal on my exchange still, but I’ve got a link to PayPal of what they do not accept and I’ve got it in bold print following PayPal’s rules of what I don’t accept.