Good catch. I didn't even notice this while reading the grandparent comment. But I've seen people debate this fact, or rather the fact that 0.9̅=1, for days and weeks on the internet.
Wow, you just pushed me and my girlfriend into a heated debate regarding this. Is there a list anywhere of similar unintuitive math properties/facts?
Hmm... I guess division by zero is sort of similar. And imaginary numbers? The wiki article has some good discussion on it: https://en.wikipedia.org/wiki/0.999...