I think it pretty normal and reasonable if you/family have means to get or give loans as a family rather than from the bank.
Obviously this wouldn't apply to terminally unreliable or bad with money family.
But why would you do this via a bank, when you can stay within your community?
I'm not sure if this is a cultural difference or class difference. Is this something that you would do, or do you consider this unreasonable and crossing a boundary?