Personally I look at the $ in my BOB as a tool.

I keep $1,000 in it broken down as follows .

$10.00 Quarters
$20.00 Ones
$270.00 Fives
$700.00 Tens

Hope this gives me the ability to get what I my need (gas , food , lodging etc ...)Hopefully I will never need it , but it is there if I do.