I hang on to my old iPod shuffles and nanos with clips on them, and have paid to get them refurbed. It's just so easy to clip them onto my shirt and go. The alternative is... what, to put my gigantic phablet phone in the small pocket of my running shorts?

I shouldn't complain too much, since there actually are a fair number of modern small dedicated mp3 players that can clip on to your shirt (although none of them that I know of are quite as unobtrusive and lightweight as a 2nd gen iPod shuffle).