When I was working on developing a site, before it had its own domain setup, I used FB like code for another domain just so it would work. It was a popular domain with tens of thousands of likes. I didn't change it right away while I got the site up, one of the early testers was super impressed how many likes my site had though. Despite being connected to a completely different domain. It was social proof that was never actually checked. I updated to my own domain and nobody has ever cared since, sadly.