What's the problem? This is the same as anyone buying something
and then selling it at a profit? Exactly what would be the criminal
charge? Rampant Capitalism?
If he does manage to sell the puppy at $2000 then I can only
presume that it is going to a much, much better home. Probably a
terrace.
Honestly, don't the police have better things to do. I mean, low
crime doesn't mean no crime you know 
When you adopt a dog, it is understood that you do so with the
full intention of raising and caring for the dog and not for the
purpose of making money....
It probably is not a crime, unless a contract was signed
prohibiting the sale of the dog for profit, in which case legal
action may be taken..... but what the fella is doing is certainly
unethical.
At the very least, the advertisement is one of
misrepresentation.... he said in the ad that he paid in full for
it, which is certainly not the case.