They tell their engineers to interview those people, then make hiring decisions based on aggregated and distilled feedbacks from those engineers.
1. Making key hiring decisions is hard: coding experience lets you better see how a potential hire's technical strengths, weaknesses, and opinions intersect with personality traits to produce value or dysfunction.
2.Coding experience helps you understand different kinds of value - it's very hard to explain to non-technical folks that while a developer is brilliant and productive, he's not careful enough and six months down the line we're going to be buried in tech debt if he's allowed to keep going.
managers thinking they know better than their reports is the source of basically all team dysfunction in tech