I replied to the longer thread, but thought I'd try to answer your questions directly. We did this excursion in July 2017. We LOVED it. I'm really bad at guessing numbers of people -- maybe 125 on the boat? There were enough indoor seats for everyone. They provide binoculars, and they had a naturalist on a microphone pointing things out and answering questions. You could go out on the back deck as well. As I recall, donuts, coffee, tea and hot cocoa were free, and then there were larger food items (maybe sandwiches and hot dogs, as well as some salmon of some kind) that you could purchase.
We got so close to everything -- whales, the waterfalls, they pointed out mountain goats, and of course the glacier! Plus it was really cool to pull up to the Wonder right near the glacier to disembark. Our group was 14 people from ages 4 to 74, and we all really enjoyed it.