I've harassed some friends into wearing helmets.
Now I don't recognize them anymore. On the plus side, everyone looks better without an open skull fracture. I like brains, but I prefer them inside the skull.
It's weird, seeing familiar people when they're either suited up or not suited up as expected for bike rides.
But, yeah, carrying a helmet without wearing it ... y tho? Dangling from the bar is just gonna affect the balance or risk getting snagged on something.
BTW, for those hipsters who bought Bern or Nutcase helmets that look like bowling balls with useless tiny vents, and then don't wear 'em because they're freaking hot... tell 'em to pony up a few more bucks and get a POC Omne Air Spin. I got one a few weeks ago for casual rides. It's basically the same kind of helmet, but with excellent ventilation. Really scoops in the air. It's so comfy I'm wearing it on some road bike rides. I may get a POC Ventral or Octal now that prices have dropped on the older models. POC's skull shaped styrofoam beer coolers are awfully expensive.