The extra profile fields are set to be private so only the person who owns the account and the board admins can see them. That's why you don't see it on anyone else's profile when you browse the forums. You can verify this by logging out of the board, then looking at one of your posts as a guest -- you won't see those profile fields in that case. So in reality, they're already invisible to 99.9% of members.

Underneath my member number there is some information I don't want to be listed every time I post. I has spambot registration, answer to question is 3 and daily e-mail updates. How do I delete that information? Please respond or e-mail me. Thanks.