DD15. DD13. DS4. DS2. DS4 months. That's five kids, three age four and under (and the four year old will have been four for one month as of our trip). So no, two umbrella strollers won't cut it - baby will be too young to use an umbrella stroller, period. He'll be carried most of the time, but the double will allow him to lie down and wiggle a bit while the four year old takes a turn walking (or we perhaps carry one of the smaller boys).
I think that you should contact Disney (
wdw.guest.communications@disneyworld.com) with your idea of banning us from stores, but graciously allowing us to use our stroller in outdoor areas of the parks. I'm betting that Disney will see it your way - they don't actually want the full $2500 or so that my family of seven will end up spending on incidentals, souveniers, and such during our eleven nights at WDW.
Sure, if we keep the stroller outside - which means that we'll have to load/unload the kids on every gift shop, which means that we'll just not go in them all - it will cut down on our spending, but I'm willing to bet that Disney is happy to forfeit our money - and money from other families with young children - so that we don't possibly inconvenience you.
You ought to send that email today. Maybe even organize a facebook group!