Many employers see tattoos and peircings bad for buisness. It is frowned upon because that is not the image that the store wants to set out.
Many people porcieve having peircings and noticeable tattoos as a way to draw attention to yourself.
Employers do not want more attention drawn to a person then their merchandise.
Now Hot Topic, for instance, wants a certain look and feel put out about it.
The scary store that old people have heart attacks just looking at.
They sell the merchandise, studs, gauges, rings, ect., and the employees having that is simply a way to advertise. Every store and person has a certain appeal and image it wants to present, and being "different" simply will not cut it in the work force.
It does distract people , it is not natural, and it is not part of your body. Therefor adults will complain.
Fake boobs may not be natural, but boobs are a part of your body. Making them bigger can be a distraction, but its a normal distraction.. Hooters, for instance, hires pretty girls with big boobs. Why? Well look at all the men who love the "chicken wings" there.
Everything an Employer puts out is supposed to porcieve a certain look, image, and feel to its customers. Nose rings, gauges, and pink hair isn't what the buisness wants to be remembered and known for.