Good luck hosting a marketplace for say, foss apps, with this requirement set forth by Apple:

>Do either of the following: (1) Provide Apple a stand-by letter of credit in the amount of €1,000,000 from a financial institution that’s at least A-rated or equivalent by S&P, Fitch, or Moody’s, and maintain that standby letter of credit as long as your alternative app marketplace is in operation; or (2) be a member of good standing in the Apple Developer Program for two continuous years or more, and have an app that had more than one million first annual installs on iOS in the EU in the prior calendar year.

Source: https://developer.apple.com/support/alternative-app-marketplace-in-the-eu/