Charities have such a weak definition in the U.K, for example Nuffield Health is a "Charity" but you'd be incredibly hard pressed to point out something charitable, it's basically a £1B private medical club that doesn't pay tax.
I don't think there should be barriers to entry for small charities, but we should be able to assess how much actually makes it to the "cause" at a glance.
There's so many places that could benefit from one of these and I don't just mean pubs. I've seen all sorts of shit systems to do the same thing, taking people's names, giving people buzz tokens etc, all fail under high demand, many assumes the queue up to the point of order is orderly.
Not only are queues and "pre-queues" full of sociopaths, willing to do the chat and cut and on the other side of the spectrum people trying to stop queue jumper entry by attempting to climb into your back pocket.
The number despencer has so many advantages, you can place it ahead of your actual queue (if you have one, with the number system you don't actually need one), this way chat and cutters can't jump the queue that can still chat but they can't cut, there's no issues with pronouncing weird names or having two people with the same name, it's not trying to be your pal, you are merely a number to be efficiently processed in exchange for currency.
It also allows for some kind of control over queue size and could help prevent situations where people are queuing for something that's about to close half way through, no more tickets means you can't join the queue, there's the possibility for DoS but can easily be solved by taking the ticket dispenser at a closer proximity to staff.