Login issues when using different email

Hello,

When I purchased Demigod, I used the email that I had signed up (at the time) with Paypal. When I created a user on Impulse, I used a different  (my current, updated) email. After doing the whole registration business under the updated email account, I tried to login to the Internet section inside Demigod and instantly receive "wrong user/password" notification. Only when I created a new account on Impulse with the same email as the Paypal one, was I allowed to connect to the Internet section of the game. This is a bit problematic in my opinion if I want my emails to be sent to a different email and it also forces me to update my Paypal email (I am not sure how much of a simple process this is, due to the fact that the login in Paypal is actually the email).

Why would it matter if I subscribe to Demigod under a different email address in my Impulse account?

Thanks