I'm SLF. So many good points above, but some that don't take account of practicalities. Evacuate a plane in the US without your passport - you're in detention or similar until your embassy can sort you out. Have your passport - you're free to go. So, I need my passport and if I'm taking my passport I'll take my wallet, phone, iPod, etc etc etc...until '..you know what, I'll take the whole bag..'
So airlines and XAAs and AIBs, work out how to evacuate a large plane in reasonable time, permitting some important belongings to go with the passenger. It cannot be that difficult.