What does a contact form have to do with PayPal? I’ve not used PP Pro, so maybe I’m missing something. You can easily hide your email address for standard Add to Cart code, by using a Merchant ID in place of the email address or by encrypting the entire button code while you are generating it.
Otherwise, there are some methods for obfuscating an email address on your website, but none of them are failsafe.
Sounds like PP are not amenable to that solution, which of course is the only intelligent option. (I wouldn’t expect an intelligent approach from a big company, though, especially PP. Intelligence isn’t fashionable in big business.)
I think I missed a couple of things in the prior comments.
Perhaps the safest option would be to use an email address that just goes to an autoresponder where the response that it sends back to the senders of any email it receives provides instructions for using the contact form.
Unfortunately the email address has to be the same one as on my merchant account with paypal. I added it using ralp.m’s method. I’ve also contacted paypal to ask if I can remove it and explained I have a contact form which sends mail to that address. If I don’t hear back I will remove it and hopefully they won’t check back on a regular basis.
If you are going to display the email address as an image then perhaps set it up with a similar appearance to the CAPTCHA images that attempt to prevent spambots from being able to use OCR to extract the content.