New to me and I've been programming web for quite a while. I've only ever seen that final "." in DNS records, it never occured to me that it would affect logic within the site.
The trailing "." becomes practically important if you have a client that believes in DNS search suffixes (yuck!). I imagine it might have some effect in this particular case if the user-agent includes the dot in the "Host" HTTP request header and it thus evades some non-canonicalizing layer of Bloomberg's paywall thing, while still being a perfectly okay request to the rest of the chain.
You know what’s also missing if you go to bloomberg.com./? All of the ads, and the animated stock ticker. I’m on mobile so didn’t dig into it further, but I bet that all JS loaded on request from another domain (probably including the paywall) is absent or broken.
The site itself loads fine though, because DNS still works and whatever routing layer in their app probably doesn’t care about the domain, just the path that follows it.
I once got a verbal C&D from a Novell web dev because they answered to any domain and I pointed (as a joke) a domain to their IP. Google ended up indexing, and customers were asking what 'reallystrangedomain.com' was when they searched for Novell error messages.
They asked me to stop 'mirroring' their content, and didn't understand I was just pointing my domain to their servers. I stopped, but part of me didn't want to.
It shouldn't. It is the fault of hacky protocols like HTTPS that conflate routing with identity. If we had DNSSEC and IPSEC from the beginning, it wouldn't have been necessary to do it on application level.