Agree, I've been doing this for decades. It's free, and kills ants in the ground too. People who feel the need to "apply something" to kill weeds seem to love the idea that it could be something free and without any packaged substance or concoction at all that they don't really know is safe to put on the ground where their pets and kids play, and often near where their food grows. I rarely need to use it because I'm on patrol for weed sprouts 3-4x per week but it's reassuring knowing this tool exists, especially after moving. There's always some established things that one wants gone.
It's much easier to pour boiling water on a patio or path than to try to pull weeds from cracks because they almost always break and leave the root in the ground.