In my own experience fragrance SA's tend to fall into one of three categories based on their own relationship with fragrances, their ability to provide customer service and how they view customers.
The bad-a bad fragrance SA are those that just happen to work at the fragrance counter. They don't have a relationship with fragrances, and worse, they suck at customer service in general. They tend to look at customers as either immediate buyers or time wasters. These are the ones that will push frags, and when you ask for a second or third frag to try they become frustrated that you aren't buying and loose interest in you as a customer. They behave as if you asked them for a squirt or sample out of their own personal bottle. 85%. These are the ones that I attempt to avoid, even when I do decide to purchase something I go find someone else who can provide better customer service attitude and purchase the frag right in front of them, no matter how small the commish may be, I refuse to give this type my business.
The good-these are those SA's that may or may not have a relationship with frags, and honestly they don't need to as they have excellent customer service skills. They understand that some people are just shopping, and not necessarily buying, but at any rate they do all they can do to provide good customer service. 10%. These are the type that usually are able to learn from knowledgeable customers and become even better at their craft.
The great- theses are those fragrance SA's that enjoy fragrances, those that are able to ask questions about your preference in notes, types and what frags you may have. These are those that not only understand when you say to them "let me walk around with the scent on for a bit, to see how it develops", they may actually suggest it. They are the ones that, IME, offer samples, will take and exchange contact info, will call to let you know when new stuff is in, etc.. These are the ones like the girls at the Guerlain counter at my local NM. Whenever I go to NM to do fragrance testing/buying I go get one of them regardless of what counter I want to patronize, because I know that they will provide an excellent experience.