Never had a problem with alcohol in domestic MCE, I just happen to be extremely lucky with crews that proactively give me two minis. If given only one I'll go to the back galley where they'll usually give me another drink without attitude. They don't however like handing me the Titos and the mixer directly, but rather bring it to my seat.

In your experience I believe they cut you as they're too lazy to open the cart again as you said.