Change iOS in-app-purchase price to free? How to reproduce what an app has done?

Question

iTunes Connect doesn't seem to offer a free tier for in-app-purchases. So how does this app get all IAP prices to free?

Other SO posts talk about changing the price, but none address changing the price to free like this app did.

app in question (no affiliation): https://itunes.apple.com/us/app/quick-4-minute-workout-tabata/id803491681?mt=8

Answer 1

It turns out this is possible for non-consumable IAPs. As below, someone was able to set the Price Tier to Free:

Answer 2

Some IAPs may become free while others may not, as Crashalot introduced. So here you have a table of what in-app purchases may become free and which ones may not.