If you're using it to talk about "market penetration" or sales... it is decent. Some people who aren't that mature might giggle or laugh since it's used to talk about having sex usually.

It's used generically in many areas. Only with a sexual context would it give you any worries. The nail missed the stud and penetrated the desk. Th epeneration was about 1cm. . We've failed to penerate the Turkish market to any significant degree. . The latest offensive by the rebels was to penetrate 400km into the goverment area of ... . All ok in normal conversation. . Also used as a techical word regarding sexual practices. You claim he molested you: I understand, but we need to know whether there actual penetration? Take care with this meaning :)

Depends on the retail job and context. Most likely no though as that word is mostly used to describe the act of having sex.