Why can't we import mail/contacts from one Gmail account to another?

While I am unsure, I would assume that they would like you to maintain one profile and one personality. Since you've developed a profile of tastes and preferences, they can serve you more contextual and targeted ads (and get paid more to do so). They know what type of newsletters you subscribe to, where you shop (based on receipts), and how often your mother/in-laws bug you about life. They may have placed your account in a certain demographics or ad groups. Two accounts would dilute that money, confuse their demos, and decrease possible revenue. Pandora used to face that problem when they only required e-mails to register. Then, again, I don't know. It's just an assumption. I've encountered the same hassle and I remember being perturbed as well. But, Gmail is free and so far superior to other free e-mail accounts (to me) that I forgive Google.