It might be pretty much universally resented, but tipping culture is a cold, hard reality in the US. Servers make their livings on tips, there's no way around it. Sure, we'd all love to live in a world where everyone makes a living wage and the burden is shifted away from the consumer and onto the business owner… but that's not the world we live in. And this isn't one of those scenarios where you should "be the change you wish to see in the world." If you don't tip, or skimp on tips, you're not "sticking it to the man," you're just disrespecting your server.
As someone who spent a good amount of time in the service industry, I know exactly what that feels like. So thank goodness for heroes like this generous person who swooped in to prevent a bad tipping situation. But little did she know, it would backfire in an interesting way.