I have no experience with Payday loans directly or indirectly. I have done a bit of sleuthing in my time, long ago when I thought it mattered (it didn't).
I don't think it's surprising really. You mentioned once that your cousin who is a police officer found him in a truck in a parking lot at 10:30 at night with a woman. When questioned your Husband made a crude remark about it.
He has a history of taking hundreds of dollars every week from your bank account.
Is he using drugs? Short of actually catching him taking them there is no way to know, unless he gets caught of course.
He sponges off his parents, lives with another alcoholic (Brother) that is a member of a gang. He has a night time visitor woman, he is an alcoholic that drinks a lot.
Aside from the sponging off the parents, all of this takes cash. Who knows what he's in to.