Turtlequest;
I don't own a pet store but I do manage the reptile department of a rather successful small business pet store in a large city. I have been managing both part-time and full-time (school takes up a bulk of my time) for nearly six years now. Off the bat, I can tell you that owning a pet store is no glamorous task. I am sure I don't have to tell you that owning any business is a time-consuming expedition that requires much dedication and responsibility, as well as money. However, when done right, being your own boss in a pet store environment can be a very rewarding experience, assuming you hire educated, experienced employees who are truly passionate about what they do.
I'm not sure where you are located, but I am in a big city (Chicago) and here most new small businesses don't make it past eight months, pet stores included. I see small shops set up all the time, only to see them empty later. The main problems include:
1. Bad location. Having a good location is the key.
2. No credentials. It would help if most of these people had at least an Associates in Business or Marketing Management Certificate, as well as experience with animals, obviously.
3. Bad selection. Most unsuccessful businesses here specialize in dog and cat foods. Let the giant chain stores dominate that sector. Stock specialty animals/supplies.
4. Lack of advertising, and last but not least-
5. The lack of realization that a small business requires dedication. A lot of these new pet stores are opened by impulsive, young, well-meaning young adults who love animals. After a few months the idea of being in a pet store every day wears out. One must think long and hard before doing this.
So the answer to your question varies. For some, owning a pet store can be a successful, exciting job. For others, well, it can be just the opposite. Personally, I love my job. It doesn't pay great, but let me tell you, I'd rather be doing this at what I make than work as a telemarketer for nearly twice of what I make. 
Good luck in your endeavors.
Joe
-----
2.2 Solomen Island ground boas
0.1 Solomen Island tree boa
1.0 green tree python
1.0 jungle carpet python
1.0 coastal carpet python
1.0 Boa constrictor imperator
0.1 Borneo short-tailed (blood) python
1.0 CB sunbeam snake