What to carry in Disney World

Someone just posed the question "Backpack or rolling bag in Disney Parks?"
Rolling bag?!!!!!! Seriously?!
If you have enough crap to fill a rolling bag, you've got too much crap with you.
When the kids were little and I needed to carry more stuff I had my messenger bag and it was filled with all that I might need for small kiddos.
Now?
Darling husband carries his backpack always but it's never really got much in it. If I make him stop to take it off to often he gets pissy.

• Water bottles filled with ice at the start of the day
• sunblock
• rain ponchos
• small towel
• bathing suits for each kid  
• whatever we purchase goes into his backpack.

I carry my very favorite Day of the Dead fabric shopping bag and in it I have my

• First Aid kid (Bandaids, Tylenol for adults and kids,liquid bandage, antibiotic ointment, Q Tips) 
• Package of tissues
• Wet wipes
• Purell
• Chapstick
• Mints
• IPhone
• Camera
• Wallet
• Gallon sized ziploc bag
• Tiny umbrella for the sun
• Ear plugs for Lion
• Sunglasses
• Hair brush

That's IT. Each boy this trip will have their own backpacks with a bottle of water, snack and whatever toy they can't leave the hotel room without this trip.
You really shouldn't need that much in the parks! Unless you have your own lunch or a huge camera or a huge camcorder or towel or change of clothing but I really can't think of why on earth you would need a rolling backpack.
I understand the "we are going out and not comin back" mindset and how you might feel you need to pack your whole entire room with you but you really DON'T.
Disney will have whatever you need.

I would go insane trying to pull a rolling bag around the parks. I wouldn't be caught dead in a fannypack.