This is a way to talk about something that's annoying to both you and the person you're talking to. For example:
Don't you hate how he's always interrupting people?
The word "hate" sometimes describes a really strong emotion, but in this case it doesn't sound that strong.
There's another form that you can also use: "Don't you hate it when (something happens)?"
Don't you hate it when you say something sarcastically and people think you're serious about it?
This version is for things that happen more rarely.