They use a piercing gun. Piercing guns can not be completely sanitized, and it likely to tear skin. It's also likely to get stuck. \r
In some countries, such as Australia, piercing guns are banned. Illegal. If you're looking to get your ears pierced, go to a REAL piercing parlor. It may be a little more intimidating to have the needle, clamp, ect and it may take a little longer, and it may be a little more expensive, but it's worth it. You're far less likely to get an infection from it this way. You get what you pay for. \r
You also do NOT want to be pierced anywhere other than your lobes by a piercing gun. It can shatter cartilage and frankly... it wouldn't work anywhere else other than ears.