"If you use facebook login for your site then you are shooting yourself in the foot if you care about users." The vast majority of Internet users would disagree

"If you use facebook login for your site then you are shooting yourself in the foot if you care about users." The vast majority of Internet users would disagree with you here. From the user's point of view, FB login lets you sign up to things in 2 clicks instead of having to fill out forms, most users would consider that a blessing.