Paul would say it was probably cheaper when I was addicted to Gymboree, LOL. (When Annaliese was a baby/toddler, we belonged to a snooty playgroup. She never wore the same outfit to playgroup twice.
)
Yes, I was thrilled to find I could get 3 t-shirts to just a smidge more than a yard of fabric. Even at the $4/yd PRR fabric, that's less than $1.50 a shirt. But when I celebrate my joy by buying 20 yards of the stuff, well, then it's not a bargain any more, you know?
If your kids can wear Off The Rack clothes, meaning there are no shape issues and you don't find them totally revolting, and you don't love to sew, don't bother. If you have a chubby or skinny or whatever child, or you think current styles are disgusting, then it makes more sense. I can find RTW clothes I like for my girls, sure. But only in $$$ pricey catalogs. Makes more sense for me to make their dresses than wade thru the brittney wanna be crap in stores looking for something wearable. And in that case, I can make them cheaper than ordering from say Hanna or Land's End.