While it would suck to have your email and phone number handed over to (even more) spammers, a worse case scenario is that someone who friended you would download your account and use it to impersonate you and smear your reputation.

FORBES: Facebook Warnings!

Companies that use CRM to bring together relevant information in separate teams can extend knowledge about a case, customer or scenario beyond what is stored in the system of record.

FORBES: Forewarned is Forearmed: Understand your Customer before the Sales Relationship Starts