Batgirl goes to a wedding! And then that same sort of story that's told with her and Dick Grayson over and over again gets told again! Eeeeeeh! ::shrug::
So yeah, my TLDR reaction is basically just: ¯\_(ツ)_/¯
It's saying something when a LoSH character hanging out in Batman is hardly the most WTF moment of an issue.
The circus is a strange place, evident by the endless Nightwing stories that come from it.
Man, I sure wish Damian showed up in Batman books too... you know, where it'd make total and complete sense?