Wondering Why We Don't Have to Show ID to Vote in Minnesota

I looked into it some more and it appears in Minnesota and a few other states people don't have to show any form of ID to vote. I guess I'm a little curious why that is. I know there is a lot of controversary around the save act right now and the forms of ID that would require to vote. I am curious about how it works currently in Minnesota however, presumably I could vote as myself and then head to other polling locations as to not run into the same workers and vote for people who I knew that lived there that were not going to vote.

Now is that anything anyone would really do? I'm not sure, maybe some people but likely not a large amount, idk. Can someone tell me more though about why no ID is required? Thanks everyone.