This. And if they don't want anyone with snakes to adopt in the future, that's something they need to put in the agreement so that snake owners are aware before they even walk out the door with the cat.
SDA and Reinz have good points. Adopting or buying cheap animals to use as bait for dog fighting is a pretty big concern, which is why it's usually advised to charge some sort of rehoming fee. Good rescues also don't want the animal to be bounced from home to home if it isn't a right fit: Much better for everyone involved if the right family is found first, rather than through trial and error. Even a lot of breeders now require that one fill out an application, with questions that very closely resemble those rescues use. However, some can be a little too nitpicky. It doesn't make much sense to ban snake owners from owning other pets simply because they have snakes, especially smaller varieties.