I went to Europe for 6 weeks once with just a rucksack. It was fine, you just wash things out in the sink each night.
Went to England as member of a choir and took just a backpack then, too, for 12 days. That was fine, too.
But would not want to live out of a rucksack in my home. That would not interest me. It would remind me of descriptions of life in prison--one bar of soap, one toothbrush, one book--everything supplied for you, and free food and health insurance of course. But yuck.