The reason that's fine is because 1 - 1 can also be written as 1 + -1, i.e., "one plus negative one." It's not that he's adding symbols that weren't there before; he's just revealing the implicit operators.

I can't tell — what's Rhode Island's famous brand?

What's this from?!

I'm 22 and still too old to get it. No idea what's going on here.

So how can we avoid it? Just keep our financial information off Facebook?

Not at all. I think Brave received way too much credit as a ground-breaking movie.