I'm not sure what you mean about being offered red GTP's ? The vast majority of GTP's in this country are from overseas stock and that is common knowledge. Red babies aren't uncommon and perfectly legal.
I think some animals are just not meant to be kept as pets. I had someone offer me red green tree pythons, ball pythons, cougars, fennec foxes, monkeys, tigers and loads more. I mean honestly what would i do with a cougar? Yes it sounds coll it theory, but the facilities to hold it, the exercise, food, and im sure it wouldnt be very cuddly at 2 yrs old with huge canine incizes. I had someone else offer me a fur seal they caught off the aust coast in a net - idiots got fined a whopper of a fine! Some animals i think just shouldnt be kept as pets for the average joe bloggs. As for exotics, - NO exotics should be allowed in australia except for zoo's. Cane toads, rabbits, red earred sliders are a good example!