ya I agree. I don’t feel the pressure to respond back. but often I do so because I want to. and chatting makes the experience more interesting

Yes! I'm surprised this one didn't come up earlier. I always find the users who make a point of doing this to be very classy. 

Of does not feel like there is much social pressure to do so, though. In fact, I can't remember a time I saw someone get annoyed that the OP didn't respond. But maybe I just miss it.

Scoresby

It isn’t obligatory but responding to comments on your posts is not only polite, but often broadens your worldview