I now know why the 5 day weekend cruise to Mexico is often called the Booze Cruise...way more people 30/40ish, definite party crowd (but in control given one or two exceptions) and definitely a constant level of drinking. Not Princess usual crowd but extremely fun! These short jaunts on Ruby Princess that leaves Thurs afternoon and basically back in time for work Mon am seem to be gaining in popularity.
We did a lot of the 3/4 day cruises a couple of years ago out of San Pedro. We were on the Golden and Sapphire Princess. They were so cheap you had to go. It was aGood time. They were booze cruises too.
I've done a few since I live in South Florida. NCL overs a 3/4 day cruise all inclusive cruise. Booze is included in the cruise fare. Now that's the Booze Party cruise.
If you think the 5 day cruises are party cruise try the Friday evening to Monday Morning cruise on Carnival, those are real party cruises.