I'm late to the game but I'll post anyway.
I don't see why mixing the pancakes in a Ziploc wouldn't work, but use the freezer bags instead of the storage bags because they're heavier. I might have to try that myself.
Also, if you have any space in the cooler or fridge to stash the leftover pancakes, just make them all at once and then eat the leftovers the next day. If you have a toaster, pancakes reheat well in a toaster, or you could reheat in a frying pan on the stove. Or if you don't mind eating them cold, that would work, too.
Jelly or jam make a good syrup if you add just a little water to get the right consistency. If you have a microwave you can heat the mixture in there, or in a small pan over low heat, watching it carefully so it doesn't scorch. It saves having to keep a jug of syrup in a fridge with limited space. Honey is good on pancakes, too, or just slather on the jam or jelly, which would also work on cold pancakes.