Yeah, without QR codes you need to keep URLs short and clean, or customers won't type them in. With QR codes you can seamlessly pass all the tracking parameters you want. It's the main reason companies have been pushing QR codes in ads for years, since the CueCat in 2000.
I'm astonished that they seem to have picked up traction the last couple years.
Yup this is what I use it for as well! It's been very handy for when I want to text a link to an article I've read on the work computer (which doesn't have iMessage/Discord/chat apps)
Maybe some people do. But if you don't use this feature, ignore it. The button being there doesn't affect your use of Chrome, does it? And if it does, it might be time to switch browsers.
Maybe it’s intended for marketing persons? E.g. when you need a link for use on a poster and stuff like that.