I think this is a good premise... it's not too broad---so you can get your point across in a fairly direct manner---but it's broad enough that you can expand on it a bit.
Thesis: Because pet stores are supposed to supply correct information, and yet, don't in the case of many reptiles, they continue the spread of improper husbandry and ignorance.
Point 1: Grab a care sheet from here and grab one from Petco and compare them. Say how the wrong information on the care sheets given out at big chain petstores causes many reptiles to be ill cared for.
Point 2: Ask people on here if you can use their stories about being misinformed and coming here to get the right information---and perhaps, how at first, they struggled against it believing a petstore couldn't be wrong. You can explain how coming to an online site such as this can cause a person to take the right steps in helping their animals.
There are many different routes you could take this. How long does your paper have to be?
Sorry, I'm an English major... this is the kinda stuff I LIVE for lol!
Point 3: