Could be a deadly surprise if the thief opens the tub with the rattlesnake in it.
On some level, I feel like car thieves deserve all the bad karma they can find, but on the other hand, leaving a vehicle unattended and running is sort of asking for it to be stolen. I mean, really, was it absolutely necessary to stop at Walmart while he still had the animals with him? Presuming it was absolutely necessary to stop, it's not like it's winter; I doubt the vehicle's interior would have cooled to the point where it would be dangerous to the animals if he had shut it off and locked it unless he was planning to be inside for a LONG time. I hate to be that guy, but it seems like the reptile owner made some poor decisions and is now paying for it.
Don't get me wrong - I sincerely hope his animals and his van are returned to him safely, but this seems like it was avoidable.