I just recently did this and thought it was a lot of fun!
I have been on friendship boats across World Showcase, but you really get to appreciate all the details of each country better this way. I for one never knew/saw a boat docked by America, etc. Snacks were the same as previously mentioned: various chips, pretzels, cookies, brownies, water, and soda. You can also order from private dining at the YC/BC, but we had a late breakfast at Ale & Compass. My captain also shared a lot of information about Epcot and Hollywood Studios. My birthday was this week and the boat also had a banner and balloons and numerous people were waving and shouting happy birthday throughout the entire boat ride.
Our boat ride was also 90 minutes which is different than what I read online and was told over the phone. You make two trips around World Showcase, then go all the way to Hollywood Studios, and dock back at the YC.
I would definitely do it again!