The tyres on the i3 rely on the contact patch being longer (because of the large wheel diameter) rather than wider (as seen on most modern cars), if you do the maths the contact patch is quite similar to other cars on the market.
An article on i3 wheels/tyres – https://www.bmwblog.com/2015/04/24/bmw-i3s-tires-more-important-than-youd-think/