Building in this space, and the thing that keeps surprising me is how few apps reply including apps that clearly care about their users.
So I'm curious what the real reason is:
You reply to everything
You reply to the bad ones only
You used to, then stopped
Never have, and it hasn't hurt you
You'd like to, but the reviews are in languages you don't read
That last one is the one I keep hitting personally and I'm not sure how common it is.