In fact, taking something like that on a multi-day hike is a good way to earn yourself a Darwin award.
All of which is a HUGE problem on a multi-day hike.
Understand what your gear can and can't do. I have a really nice (Patagonia) backpack that I take with me when I go into town on the weekends and to work when I don't need a laptop. It is also great for going to the gym and for multipitch climbs where we are maybe ten minutes from a car. It is durable as hell and I can tie a small static rope to it if I am going to go up a chimney.
But it is tiny and it doesn't have a particularly secure top (draw string closure with a buckle). So if it is raining, I leave it at home. And if I am more than ten or fifteen minutes away from the car, I'll take my normal hiking backpack with me so that I can actually carry supplies and extra gear.
Does that make it bad? No, not at all. But it does mean there are some huge caveats to it.
I might as well accuse you of being obsessed with calling me obsessed because you bothered to reply.
When did we reach the point as a society where actually elaborating on a point and responding to someone is "fervor" and "obsession"?
Fair enough. I just found it odd that you're repeating yourself to every single person who replied to you. Or maybe I'm the odd one for noticing? That's a possibility too.
But apparently we are both just obsessive people for having a conversation and not ignoring people