You haven't the foggiest clue about what you are talking about.
Do you then pay for your resort bill in cash after your band-charging-spree? No, you pay it with...a credit card.
The largest part of credit card swipe fees are a percentage of TOTAL VALUE. Usually 2-3%. There are some antiquated low-volume systems (something that a tiny business like your barber, or a no-brand mom and pop store) that have a small surcharge ("minimum fee") on tiny transactions but a merchant as large as Disney isn't likely paying that to begin with. If their deal with their processor is so terrible that by some chance they do, it's a small amount compared to the overall paying of a flat percentage of sales.
So if you pay it all at once at the end of your trip or pay out each transaction, it all pretty much adds up to the same overall fee for Disney. Any possible tiny savings would take 300-400 years to even begin to make a
dent in the 1.5B cost of the system. And the kicker is, all these charges are already rolled into the prices of everything they sell - so everyone is paying for them, even if they pay cash.
But let's say, by some rarity you are super-unique and do pay the end bill with a different form of payment - the pittance saved by Disney on the subset of folks who don't pay with a credit card from the subset of folks who even have a magic band is going to be infinitesimal.
What I haven't seen anyone mention about the band system, just like the resort charge before it - is that any illusion of safety is just that - illusion. All the fancy credit card fraud protections that are in place for most card holders
do not apply in the same way to Disney keeping your tab and charging it all at once. It's one charge - that you can dispute, or not, but you are going to have a hell of a time disputing the entire thing vs. a series of smaller transactions. Not just for fraud, but for things like item replacement/warranty privileges a lot of cards have, as well (if, say, something is broken in transit home, etc.).
Basically, you are fully trusting Disney to add everything up and keep careful records, which to get your credit card company would likely have to subpoena. Most of the current legal protections you enjoy are rendered moot in this case.
But hey, you can bling out that bracelet with pretty jewels and save your wrist the agony of having to take a credit card out to pay for your transactions, so that's all totally worth it.
It's not. It's simply technophobe/technoilliterate illusion. Just like folks who think sending a check through the mail (which is, by far, the most dangerous thing you can do with your financial information - using the data on that check, which never actually goes to the company you are paying anyway - it goes to a "lockbox" that services 100's of companies, someone can clean out your bank account via wire, at which point it's nearly impossible to recover) is "safer" than paying a bill online.
He's the type that Disney is banking on, though, quite literally - but as we've said from the beginning, the amount of foolish folks that actually spend more and fall for all this, and actually spend a few percent more than they did to begin with, are simply inconsequential financially overall. Even if every single person willy-nilly increased their spending due to the novelty of an internal currency (which is never going to happen, as not everyone is ever going to have a bracelet), the couple of percent increase still wouldn't be anywhere near worth the cost of this system, unless, again, it's amortized over hundreds of years.