You could also... just... not get them anything unless they earned it according to rules that they agree with and believe in.
Of course that would require a lot more parenting than buying things.
I think the previous comment was more about second hand, and free options compare to running out to buy them new from a store; not if the parent should/shouldn't get them anything.
I think the previous comment was more about second hand, and free options compare to running out to buy them new from a store; not if the parent should/shouldn't get them anything.