The couple headed back to a strip club, Crazy Girls, Sunday night in L.A. ... smacking butts instead of bartenders. It was their first time in a gentlemen's establishment, that we've seen anyway, since Cardi's last visit. Ya know, the one that got her arrested and charged with assault for allegedly ordering a beatdown on strip club bartenders.

Offset was armed with a seemingly endless stack of Washingtons in their VIP section ... and Cardi even got on a pole and started twerking for her man. What's that thing about old habits?

Smart move on Offset's part -- everyone knows the dancers give you way more attention when you have a female companion. Just take a note from Offset, and get ya girl some roses while you're at it.