Never heard of anyone using one of these, but I use an Amphipod runner pouch for some EDC items not carried in my pockets. Small and low profile.

Several times, items come out of there to"save the day." Usually unprepared parents. I was at a couple of birthday parties where the parents did not bring cordage for the kids' piñata. Out came cordage, and piñata disaster averted. Another time, someone I did not know was having a birthday party for their kid and no lighter for the cake's birthday candles. Lighter came out... They did not even offer me a piece of cake after. How rude.