My thinking on the no bear can if all food is eaten on day 1, is that bear cans are not required for day hikers, so why should you need one if there is no food at the end of the day 1? It would be ridiculous! Bring a bear can and put nothing in it?
Another way to look at what we see as needed is to look back at what we brought in the "old days". I spent many summers in the Wind Rivers, in some horrible weather, weeks of rain, snow, horrendous mosquitoes. We only had wool pants - no rain pants, no long johns. Just thick sturdy warm wool pants. Our ponchos were knee length. Sometimes we got wet. We stayed somewhat warm in wet wool. We eventually dried out. We had no tents - just tarps. We went in groups (solo trips were rare in those days) and shared much of the group gear. First aid supplies were minimal; first aid training was extensive. Our "items" were heavy, but we really took less items than most backpackers take nowadays. Walk into REI nowadays, and you would think you need 100 items to go backpacking!
John Muir would go out for days with a heavy wool coat and hard tack in his pocket for food. I read a book about John Muir's childhood - people in those days grew up simply accepting a lot of discomfort as the price of living. They grew up spending a lot of time outdoors (farming) so being outdoors was simply normal. Their bodies were much more acclimated to hot and cold temperature variations. They did not seem to fear getting wet- just took it for granted.
I also think they were less concerned with "safety". A lot of other things killed people back then. Many children never even lived to grow up. I think they had more of an attitude that when your time comes, so be it.
So with our modern "choices" given by a multitude of "stuff", media telling us that we absolutely need it, our modern aversion to risk of any kind, and our softness both physical and mental, it is no surprise that we feel it is difficult to go out for one little overnight trip with 11 items.