With kids aged 7-13, I think you have a few options....
(1) Minimalist. I bought a small (tiny) cross body purse at Walmart for less than $10. It holds our tickets, our fast passes, some cash, my camera, extra batteries for camera, and my phone. Then I spent $10 for a carabiner clip at Disneyland for a water bottle. Viola!
(2) Kids old enough to go without a stroller are old enough to carry their own bag. Then, each person can have what they think they want/need in their own bag, and mom and dad don't have to carry 5 coats.
(3) No bags. Lockers are on Main Street and Beuna Vista Blvd, as well as in the esplanade. A little less convenient, but a lot more comfortable in my opinion. For me, I *hate* (HATE HATE HATE) Anaheim water. So, I actually bring in a gallon of water and keep it in there with coats.
--Mimi
Mom to Lala (2004), Bonus Mom to Big Sis 1 (1991) and Big Sis 2 (1992)
Grammy to Big Kindy Kid (2011), Big Pre-K Kid (2012),
Grandbaby Appendage (2014), and New Baby Grandboy (summer 2017)