I have 2 email accounts that I use--my Gmail and a mail.com account. I do not want my accounts to get new mail unless I tell it to. My Gmail account is behaving itself, but my mail.com account keeps notifying me of new mail. (It gets lots of spam, so I don't want to get notified with a green flashing light every time a Nigerian prince wants to give me a million bucks).
I have data push turned off, I have my email fetch schedule set for manually, I have sync turned off, yet it still checks periodically for mail. I'm sure if I disabled background data it would stop, but then I wouldn't be able to use other functions, such as the market.