Frank,

I think that the "ugly issue" is an issue and a business risk that just needs to be accepted depending upon the user base of the web site/app. If the typical user is going to expect to employ his Facebook or Twitter or whatever ID for access and if the publisher wants the site to grow, you just do it. The uglier issue is a site in which an investment is made that is not well accepted by the market that it is trying to capture because it does not confirm to expected norms.