Trying to achieve a checkout with no address at all specified- much the same as a local bricks and mortar store really where you walk in, buy something, leave: cashier never requests a shipping or billing address because standard tax is applied to the product regardless.
In our config, tax is applied to the billing address, and we have tax applied to products and hardwired the country of current billing/shipping address to the same country as the tax configuration.
So up to now, we've always requested an address (for shipping and billing) but for a downloadable product, requesting any kind of address is meaningless (we're now just a POS). How to save an order where all addresses = 0? Currently, I'm getting an error raised on SetOrder() where no billing address.
The INSERT statement conflicted with the FOREIGN KEY constraint "FK_COM_Order_OrderBillingAddressID_COM_Adress". The conflict occurred in database "KenticoCMS7", table "dbo.COM_Address", column 'AddressID'.
Based on that, there doesn't seem to be anything I can get around with a config setting.
The main question I guess would be: how badly would I break the integrity of the Orders subsystem if I remove that Foreign Key? :)