Might be a good thing, many people find the butchering easier if they don't name them or identify with each one as an individual. Unless you are keeping one to breed, averages may work OK for you.I have no way of knowing which chick is which from week to week,
I see people were posting while I was typing. So, yeah, no leg bands. But food coloring is passive. Different colors on different body parts gives you a lot of flexibility in marking them. A red on the head is different to a blue on the left wing is different to a red on the head and a blue on the left wing. Or yellow or green. You may need to renew it as they feather out but it is definitely doable.