Facebook does this too. I'll go to a link to a facebook page and be greeted some seconds later with nonsense about having to login. There's also that facebook login box that covers the bottom of the page.
Yeah unless it's a business, even then, you're pushed to sign up for an account to message the business. As a business, I would be weighing my options here as your Facebook page is often one of the first to show in the results. Not long until Facebook starts advertising other businesses over your business page.
