Have people been trained or deluded to "always get the app" when it's not necessary?
My biggest problem with web-apps is that you can select parts of the chrome half of the time.
For example I could be in the garage, out of engine oil, phone out, scan the barcode on the old one using the camera, oil turns up on my doorstep first thing the next morning, sometimes only ten hours later if I do it in time. Takes literally ten seconds tops.
Not so strange is it? See how it saves time and hassle compared to the laptop?
Also some people use phones and iPads as their primary or only computer. I would guess especially less wealthy or technically literate people. And the apps are often much more accessible than the websites on those devices.
I get your point about the Amazon app if you use it all the time, you're signed up for it, and the workflow in the app is seamless. But the Foot Locker app? For a once a year purchase of tennis shoes?
I'm still thinking that people install these niche apps because they've been indoctrinated into it. Like the way people type "ebay.com" into Google rather than typing ebay.com into the address bar.