I'd be more worried about them wasting the feed. The more feed available (to mine), the more they waste. Maybe you can put some cake pans or something under the feeders? Then at least if they kick it out, it won't go far. You might want to look into some kind of a 'block', something that is stuck together, so they can't spread it. That would give them some extra, in case they would run out of feed. I would also put twice as many water bottles than you think you'll need. My jumbos' bottles have to be filled daily (for the one with the pop bottle water top) and every 2 days for a regular rabbit bottle. I have 11 birds in the cage, and they have both these bottles.
You might want to think about putting the cages on the ground while you are away, at least any dropped feed will be there for them to get.
If you use a small hanging feeder, like 5-10 pounds, that would hold them for a few days, but you'd have to worry about them wasting it. I don't know, good luck with them. Water is the most important, if they are out of food for a day, it's not going to kill them.