@Helen and Mario
I think @Geoff22's idea is that is an optional tool that hosts can use if they so wish and the host decides which chargeable extras they want to include or not. If you don't want to offer snacks or daily towels, you don't have to, but if you do, you are able to offer this as a paid service when the guest books. The guest can choose which extras they want and the cost is added to their booking, so @Geoff22's idea is designed to cut out the "chaos of chasing them to pay up the extra services".
The only problem I see with this is that certain guests will choose not to tick and pay for extra services but will mentally register that the service is available and expect it for free. I have hosted those kinds of guests, so I can see this happening.
What do you do then? You are back to square one and having to send them a request for the money, which I have recently found out, they have no obligation to pay. If the guest ignores the request, Airbnb will not charge them any money still owed to the host, even if the message thread clearly shows they had asked for the service and been informed of the cost.