The DVC fireworks cruise is only done on Wednesdays out of the Contemporary. They provide champagne and chocolate covered strawberries prior to the cruise in a roped off area for the members. The price is per person, and they do not cancel due to small groups. They have actually sent them out with only 1 or 2 people on the boat, but usually there are more on the boat. They do a maximum of two boats each Wednesday, 10 person maximim per boat. The usual snacks and soft drinks are also included on the boat. Tips for the skipper are accepted and certainly appreciated by the them, but not required. Some people do, some don't, it is your call.
The Pirates and Pals is a totally different experience which is a shorter cruise timewise, and is more geared towards the entertainment aspect of the pirate. The pirates cruise is also on a time limit, if the fireworks are delayed, which does occur on rare occasions, the pirates boat returns to the dock, whereas the regular cruise boats do not until the show eventually fnishes.
If yu have any specific questions regarding the various cruises, Pm me.