This is definitely a pun and a joke. The word "dab" means to put or cover a small amount of a powdery or liquid substance on a surface, such as someone's face or skin. The word "dabble" most likely means to splash or dip in water in this context. "Dabble" also means to do something without being totally interested in it. For example: "Guess what? Alex has started reading about politics!" "No, he's just dabbling in it. You know how that boy is. He changes interests as often as his socks!" Anyway, like I said before, it's a pun; it's a play on words that would be hard for most nonnative speakers to understand. In this scenario, "dabbler" meant that the person was simply dabbling, as in she was interested in perfume, but not that much. The person in the story was an amateur who wasn't interested in making a serious hobby out of it. Given that dabble also means "to splash", there was probably some word play here. "Dab", like I said, means to apply something to a surface, like skin or someone's face; so I think now you might get the joke. So the word "dab" was changed to "dabber" for the sake of the joke.

I use the word "daub" instead of "dab" so I failed to see the humor. The "dabber" vs "dauber" controversy can be viewed here for more linguistic fun: http://www.latestbingobonuses.com/bingo-news/2013-02-26/dabber-vs-dauber/