[threeseed]

Has been that way since day one of the iOS App Store.

It was because it was re-using the same backend as the iTunes Store which was ultimately backed by an SAP system. One that required billing addresses for all purchases (free app = $0.00 purchase).

[lern_too_spel]

As far as I know, no other smartphone app store does this. Apple could have corrected this any time in the past 14 years, but no doubt Apple figured the reduction in expected App Store revenue and decided that it values that revenue more than user privacy.