This is the way. It's prudent to treat apps with skepticism, it's unfortunate it's come to this.

I study Apple's Privacy Nutrition Labels religiously every time I consider installing an app.

I like the ones with "Data Not Collected".

I uninstalled the app recently; despite having layers of ad tracking protection, I would see my Amazon searches appearing in my social media feed in near real time, and this irked me.

I dropped their .com into a Home Screen icon, and this completely stopped (at least as far as I’ve observed). It’s definitely more janky from an experience perspective, but still easier than driving to the store.

Shopping works better on web sites because can open multiple tabs to browse multiple products. Especially important on big stores like Aliexpress and Amazon where need to compare lots of products. Desktop is better for that but mobile browsers are still better than apps.

With Firefox, yes. I wouldn't fully trust other browsers to care about my privacy.

I think you need the app to use the delivery lockers (which I prefer over home delivery)

AFAIK, the app is just the website in a webview.