What do you think of the US tipping culture?

I personally find it a bit silly. How it’s almost mandatory. People get frowned upon if they don’t ip. Whether it’s bad service or not. Even if they do tip and it’s not a lot they still get frowned upon. It’s ridiculous to me. There are some countries where tipping is offensive in itself. Or many where it’s not expected at all. If people in the US are getting underpaid shouldn’t they be blaming the workplace and not the consumer? Pretty backwards if you ask me.