I grew up in the UP (Norway). You didn't say north central or south central. Are you in Ishepeming, Negaunee, or Gladstone?

I have had several encounters with black bears in the UP but I have never come across an habituated bear. The ones I saw always ran off. We never hung our food camping unless it was recommend in the area.

If you an in an area that recommends hanging, then hang. If you think you are going to be around habituated bears then carry bear spray. Otherwise I personally wouldn't act any differently than you are and I think your friend is acting on fear. Bears are pretty actively hunted in the UP. There are not that many areas where they are protected. They tend to be pretty afraid of humans.