Not parent post but...
Imagine a scenario where friends and family are the last people on Earth you are going to ask for help. Not everyone is of the same mindset you describe.
Pride, mental health issues, family history, etc all play a part. I was homeless once, a combination of these things is what stopped me asking for help.
I have relatives who are regulars on the Sunday Times Rich List, some good loyal friends and 3 siblings. Go figure.
Time plays a factor. How long do you think they'd put you up? One month? Six? A year? Two years? Five years?
And if you pick up some bad habits while being unable to get back on your feet and living with friends... that can get you booted more quickly.
Additionally, temporarily is fine when you have prospects to lift you from having to resort to relying on the generosity of friends/family but for those that don’t, it’s difficult to ask for help (don’t want to burden those you “love”), and difficult to provide any (“want to help but can’t afford it”)