We went on a trip to CA when my son turned 1. I still breastfed some. I also brought along those formula packets that are premeasured b/c we hadn't introduced regular milk yet. I think you can get baby food at some resort gift shops. At counter service, you can usually find yogurt and applesauce. Bananas are not too hard to find. Ice cream is easy to find. For breakfast, you can usually find oatmeal. Freeze dried fruit would not weigh down a suitcase nor would a box of cheerios.
By 15 months, my son could eat most table food as long as it wasn't a choking hazard or spicy/seasoned heavily (like BBQ would not work)