I'm not arguing what is best for the customer. Just best for Facebook. It's their service an they get to do what they want. It sucks, and I wish it wouldn't happen but it does.

I know amazon does this for seller accounts, and I've run across it a few more places as well (craigslist, etc). Although Craigslist gives you the option to not obscure it.

I kind of saw the writing on the wall when the messaging platform was announced. They are trying to replace email for most people.