We have a kiddo with food allergies, so we pack food for all excursions (from home)...as a vegan myself, my suggestions are individual packs of: dried or freeze dried fruit, nuts and trail mixes, granola bars, popcorn, (GF for me) pretzels, individual packs of peanut butter and a sleeve of crackers, chips, bottled drinks, and individual packets of plant based protein that can be dumped in to a water bottle and shaken. I use the Orac Energy Greens by Paradise and they are sold on
Amazon. Costco, Trader Joes,
Walmart and Amazon are my main go-tos for the prepacked snacks.
Keep in mind that what comes on the ship, must be factory sealed...as well as when you take it off, so if you open it, you need to finish it or be willing to toss it, which is why the individual serving work best. You can open stuff on the ship and consume it slowly, but any food that crosses the threshold of the ship must be sealed...coming and going.
The extra snacks were also nice to have on board when we got tired of running up top to get something...like french fries or a plate of tomatoes...