"You can pm me or leave comment and will get back with you"
Some of us don't have Facebook.
And yet it makes me smile there are so many businesses that only register people through Facebook (as a matter of fact, after 10+ years with company BzzAgent doing sample and product reviews, they revamped their site and tried to force everyone to re-register using... you guessed it, Facebook! As the only option!)
Businesses that make you register through Facebook.
Businesses that hold contests you can only enter through Facebook.
Businesses that only have Facebook websites but no .com sites.
And small companies that post all over local city Facebooks trying to drum up business for themselves... and only have you "pm me" or leave a comment and I'll get back to you!
BDummies. Without a contact phone number, a webpage, a way to contact you besides private messaging you over my non-existent Facebook account... you are missing a LOT of potential business and new customers. :)