although we have never packed any sandwiches (because we're not big sandwich snackers) we did see plenty of other people enjoying them while taking a rest break. So, I think that if you want to bring along sandwiches you will not have a problem at all and be in great company.
In the past we have enjoyed packing chips, box juice drinks, granola bars, cookies, crackers, and the 'handi snack' type of things. There are many benches you can sit down at and grab a bite but they can get a little hard to find sometimes especially if you will be there during summer peak season. But, if you just keep strolling along you will eventually spot an empty one. I hope you enjoy!