Case:
Our iOS app offers selling of custom made recipe packages that would be created for each user specifically. For example - user buys package of rec
If such scenario isn't possible via Apple refund, are there some examples of this kind of purchase model, implemented in some other way?
In some cases you can use payment through PayPal (for example). We did it in our application where we had to take money of users and return it after a certain period. Check if you case is suitable for using third-party payment systems. Because (for example) Apple will restrict your app if you want to sell in-game content via Paypal, not with in-app purchase.
One very simple alternative would be to have your users buy virtual currency in your app that they can then spend on their recipe-package-orders. Since you are managing their virtual currency account balance, you can easily refund, give volume-discounts, etc. as you please. The only thing that will still be hard then is to have users return their virtual currency to get back their actual money.
If you get paid using Apple services (in-app purchases) then NO, it isn't possible for an Apple Developer (business or individual) to refund App Store customers.
The only option is to direct customers to iTunes Store Customer Support as officially stated in the iTunes Connect screenshot below:
To increase the chances for your customers in getting refunded you could provide them with an e-mail stating that you would like them to receive a refund which they could show to the iTunes Support employee.
As a colleague stated, an option would be to use an external payment processor like PayPal which would allow you to manage refunds, but I think this will greatly increase the work needed since you will need to manage almost everything regarding payments on your own.
Also note that this option is highly restricted by Apple to only physical services or goods and sometimes Apple does not approve apps providing services through third-party payment processors. So.. you should be very careful what path you choose to take.
If the recipes you're providing to your customers are in digital format and users receive them in your app, you can be 100% sure that Apple will force you to use the in-app purchase system.
There is no api for allowing users to refund a purchase (otherwise guess what can happen).
More info here