I've had 2 or 3 packages delayed by a day by various carriers over the last couple of years and the animals pulled through fine. So 2nd day shipping could conceivably be fine for most reptiles that are healthy to start with. But the issue comes in what if there is a delay on the 2nd day package, your looking at 3 or 4 day trip. What if it runs over the weekend, now 5 or 6 days?
From a business standpoint it seems silly to risk $100+ (your live arrival guarantee as most animals sold online are usually $100+ as cheaper ones don't warrant the shipping costs) to save $25 on shipping which is usually picked up by the buyer anyway. We carry a 7 day guarantee on our animals and for this to be a low risk venture I need to get the animals to the new owners (who could be newbies with a complete list of newbie mistakes to make on the husbandry end) in prime condition, not dehydrated by 2 or 3 days in a box. We target new / newer reptile owners (don't sell too many piebald pythons
) so I want there to be room for error as they get the heat and feeding right.