I use my BoB for 2 & 3 day backpacking/camping trips.
You're right about getting it to be more practical and useful by exercising it !!
So, what happens if the SHTF right after you've finished your camping trip, and your BOB is empty of all useful supplies?
Kind of like that Clint Eastwood movie where the bad guys jump him just after he has shot all his pistols empty target practicing.