I usually keep my badge facing in (so you can't glance at my info) on purpose if the badge has a lead-gen attendee type - e.g. founder, investor, media - printed on it. I find that having it the right way 'round makes it harder to have interesting or productive discussions because by the end of the first day everyone is pre-judging the people they meet based on their badge.

If I'm there on a founder badge, for example, it's difficult to chat up investors because they're wary of hearing the 400th pitch from a random startup guy when I really just want to talk and make a connection.

This may be more annoying for me than most because I'm often at conferences as someone's guest, so the badge type rarely matches with my goals for attending.

Then double loop will help keep the badge exactly how you want it!

I actually prefer the double clip style because I find it more comfortable, too! Just offering an anecdote that might help explain your observations - I can't be the only person who does this.

Some people don't like showing off all their information, but most venues require the badge to be shown at all times.