With Verizon yes...with AT&T's new family plans, it'll be a big difference.
A paid for/off contract phone is only $15 a month. The installment payments on a new device is $25-$40 a month extra. When it was the same monthly fee for a subsidized or unsubsidized device, parents considered it a simple $199-$299 purchase. Now it's an increased expense over time.
I can see a lot of parents encouraging their kids to take 'hand me down' phones or looking for unlocked used devices rather than buying new phones for all the kids.