Why would most people rip someone off for drugs but would return a wallet they found

I'm guessing that the people who would rip off someone for drugs, wouldn't return a wallet either. Unless there was no money in it and they were hoping for a reward.

The addiction of drugs is stronger than their morals. Simple.

Stealing from other criminals is just part of the game

They can't smoke or snort the wallet.

Uhm coz they’re dope fiends

Guilt ?