I know this isn't related to SQL Server, but it is related to security and privacy.
If an employer or potential employer asks for your Facebook credentials or for you to log in and let them look at your account, have them go the following link: https://www.facebook.com/legal/terms
There are several parts for them to see. In order for anyone to use Facebook, they have to agree to this:
5. You will not solicit login information or access an account belonging to someone else. (under section 3. Safety)
And if you are to continue to use Facebook, you have to abide by this:
8. You will not share your password, (or in the case of developers, your secret key), let anyone else access your account, or do anything else that might jeopardize the security of your account. (under section 4. Registration and Account Security)
Therefore, they cannot ask for your login information and legally use Facebook. They also cannot ask you to log on to Facebook and look at your account (that is accessing an account belonging to someone else) because in order to use Facebook they have to agree to the statement where they will not do that. They would be in breach of the terms of service with Facebook if they attempt to do so. Also, for your use of Facebook, you aren't allowed to share your password or let anyone else access your account. If they persist, remind them that this is a potentially legally binding agreement and before you could break such an agreement, you would need to get the advice of counsel, and so should they.