Many years ago in 21 and 23 it was the custom for badged chaps to sport their wings on the shoulder of the woolly pully when in barracks. Since we only had one W/P, and they were also worn in the field, most of us used a pair of press-studs to hold the wings in place on the W/P.
A new CO arrived at 21, who decreed that wings were not to be worn on W/Ps. No-one removed the press-studs from their W/P, however, so it remained very easy to tell the badged lads from the REMFs for many years to come.
I'm pretty sure that those eligible to wear wings (P) will soon find a way to distinguish themselves from the remainder.