If you supply an email address when creating a Petunia account, we will not spam you. Your email address would only be used in specific customer support situations. Unless you specifically ask, we will not put you on a mailing list.
On the Petunia server, which is used primarily for in-app purchases, we record IP addresses in the case of errors or failures. Recording IP addresses in this case is done so we can track down and fix problems. And so we can deal with fraud or attempts to bypass system security.