1. These little loops on the back of the shirt.https://leangarments.com/products/light-blue-ocbd
Yes, this is what we're speaking about.
2. Earlier, there just weren't any kind of wardrobes to hang your clothing.http://stylefellow.com/review-lean-garments-chambray-shirt/lean-garments-chambray-locker-loop/
Thus, those loops were truly essential to hang t shirts without wrinkling it.