Got it. In Cabo, take a water taxi to Mendano beach (the Office is always pretty busy) and then walk back through town.Best Bar - Giggling Marlin.
In Mazatlan, take a taxi to the Golden Zone, Set up camp in front of the Hotel Playa Mazatlan or one of the bars to the south, and then shop in the Golden Zone for stuff. Mazatlan's most notable bar would be Senior Frogs just south of the Golden Zone.
In Puerto Vallarta, taxi into the old section of PV for shopping and then hit any of the bars along the Malecon. You can beach it up anywhere along the coast there.
Have a great cruise!