That is a really good question. I am a lay Dominican and, when I was received into the Order, I was given a small, white, rectangular scapular that I was supposed to wear inside my exterior clothing. I asked myself, but nobody else, what I was going to do with my brown scapular, because up until that time I had been wearing the brown scapular. Since the brown scapular was a sign of my dedication to the Virgin Mary, and the Dominican Order also has a very strong devotion to Mary (we are required to say the rosary every day), I decided that I will just wear the white scapular of the Order instead of wearing two scapulars. I figured that by giving me the white scapular of the Order, the Blessed Virgin Mary is simply giving me a scapular “upgrade,” so that wearing the white scapular in lieu of the brown scapular does not mean losing her protection, but actually brings me closer to her, inasmuch as it elevates me to a higher level of dedication to her and to God. Well, that was just me. I didn’t ask anyone, and no one told me to do it. So, I discontinued wearing the brown scapular without any scruples. For, I did not discontinue it out of contempt, but out of my conviction that the white scapular is an “upgrade” of my brown scapular.