I want to like barefoot shoes, but they're killing me

I love the idea of barefoot shoes. I really want to like them. But they are hurting me.
I've been wearing Vivobarefoot shoes for about 6 months now, I alternate every day with regular cushioned shoes.
Every time I wear the Vivo's for my daily walk, my knees / hips / back hurt after about 30min.

I walk mostly on concrete, I think that may be the issue.

I'm in very good physical shape. I do sports several times a week and walk daily for about 1h. My weight is also not an issue.

The shoes are Vivo Geo Court, they have about 8mm of cushioning.