I thought of another reason I like them for comps… I have osteoarthritis in my hands (and many other areas too); and as a result, my left index finger no longer straightens, and the tip (the distal interphalangeal joint, to be specific) bends about 20° to the left. So when I use press-on nails, I can disguise (or at least camouflage) that problem by putting the nail on the way my finger SHOULD point, rather than the way it DOES point. (The other visible arthritic effects, like several enlarged knuckles, are less noticeable from a distance…but when you have adjacent fingers pointing in different directions, it stands out.)
(And btw, for those of you who have joked previously that I “won the genetic lottery” in certain areas, don’t forget that I also inherited a whooooooole lot of less desirable things, including very early-onset arthritis. Genetics can be a blessing AND a curse.)