Of course it's different. Only certain people can see your Facebook status.
Well who can see your Facebook friends how you arrange your settings, but I take your point that it “feels” like a limited audience.
That’s a fallacy though. How many times has something that is posted on a “private” Facebook page gone viral? All round the world in a few days?
Facebook IS. NOT. PRIVATE.
As soon as you publish something you give other people control over it, you don’t know who is showing what to whom.
The OP explicitly named her company, she deliberately set out to embarrass them.
And you never ever know who knows someone you are connect to.
For example my Dad’s best mate is CEO of the company my husband’s cycling buddy works for. We’ve never mentioned the connection to the buddy, it hasn’t come up in conversation.
It’s easy enough to imagine a scenario where my Godfather visits my house and glances at an open ipad though isn’t it?
Fb isn’t private, you have very little control over your post once it’s out there.
The OP defamed her company, publicly, and she intended to, that’s why she named them.