all you need is a number smaller than 30%. build your own or use someone else for 10%? easy choice

10% sounds very aggressive to me still

Even if you implemented the whole checkout process yourself, you'd still be paying at least ~3% to your credit card processor -- more if you're handling small payments, as most processors charge a fixed fee as well.

10% to handle the entire subscription/checkout process isn't bad at all, especially if it means that many of your customers can check out without entering any billing details.

Then high street margins for physical games would really surprise you...

The physical game store isn't charging X% for payment processing. They're charging X% to get your product in front of customers.

> They're charging X% to get your product in front of customers.

Oh, right. The app store doesn't also do that?

Retail stores have a finite and very small amount of shelf space. Publishers pay a lot for a significant percentage of that shelf space devoted to their product.

The App Store has effectively infinite space. There are so many products and search is so broken that it's extremely difficult for users to discover your product.

Rather than comparing the experience to brick and mortar stores a more apt comparison would be to throw your products in a landfill, junkyard, or extremely large flea market and expect your users to find them. Would you pay high commissions to a junkyard for tossing your product in a pile "somewhere in the back"?

No not really. Can you imagine gamestop demanding a cut of dlc purchases because a physical game was originally purchased in their store?

These are separate concepts.