You might use the web on your phone in a way that makes what you describe make sense. But most people don't. Most people use their phones on the go or where they otherwise want quick access to the important information on a website; where scrolling and zooming around a page to pull out the useful information is fiddly and annoying.
Most people, when they want more information, ie, not the basic mobile view, will use some other device with a larger screen than a phone that is more suited to comfortably viewing more information like a tablet or laptop.
I realise 'most people' probably needs citation. But I'm talking from my own experience as a lead engineer who oversees a lot of very popular ecomm sites for a company that spends a lot of time monitoring users' habits so we can boost conversion rates. 0.1% conversion increase for us is measured in millions, so as a company, we've kinda done our research.