In real reality, Danish banks are charging 0% interest for mortgages and making their money off of closing fees[1]. Also the natural rate of interest is zero[2].

Just because you've been raised from birth to believe usury is necessary for the payment system (not the economy!) to function doesn't make it so.

[1] https://au.finance.yahoo.com/news/danish-bank-introduces-new...

[2] https://news.ycombinator.com/item?id=16414199 http://www.moslereconomics.com/wp-content/graphs/2009/07/nat... (link is broken in the HN post)