I carry it with me, in some sort of bag -- a carrier bag from a shop, a backpack, occasionally a bicycle pannier bag. Parents with young children will stow some

I carry it with me, in some sort of bag -- a carrier bag from a shop, a backpack, occasionally a bicycle pannier bag. Parents with young children will stow some stuff in the tray under the pushchair. Some places have lockers, for example a concert hall or art gallery where they don't allow you to bring in various things. That does mean I avoid buying something heavy unless I'm on my way home. (I'm in Copenhagen, not Tokyo.)