Yeah, I guess so. Beyond the malicious reasons, there could just be the thought that the utility outweighs the privacy costs for the user experience. Especially considering your FB friends are supposedly people you know in real life and trust (at least more than people you might have on other IM services).
I can understand the divisiveness, but I can also imagine people working on messenger (who probably use it a lot more than you or I) being on this, and genuinely believing it leads to a better user experience for most people (see read receipts).
your FB friends are supposedly people you know in real life and trust
According to the article, this feature is also enabled for group chats, where you converse with people who are not even your FB friends.
people working on messenger
I happen to be working on a mobile messenger [0], and I can see the benefit of transmitting user location. Still, I would never implement it as an on-by-default feature on all outgoing messages. Sending a location should always be an explicit action performed by the user, for battery preservation reasons as much as because of the privacy.
your FB friends are supposedly people you know in real life and trust
If the FB developers think that's generally true, I'd say they are pretty incompetent. Even my parents, with just a couple dozen friends, have FB friends they have never met, let alone my teenage brother and his friends, who have hundreds of FB friends each.
This is usually not a problem, since they don't post sensitive information on their timeline, only in the chat to specific people.
It probably actually is a problem but most people don't realise it.
Even when people are incredibly careful people do unwittingly post things that allow others to identify them. They may not reveal much in any individual post but when you combine a few together its a problem.
1 prime example is a friend who posted an invite to a house warming party then a week later posted from their holiday abroad...
I can understand the divisiveness, but I can also imagine people working on messenger (who probably use it a lot more than you or I) being on this, and genuinely believing it leads to a better user experience for most people (see read receipts).