Is it permissible to accept free candy on the occasion of Christmas from a store where I subscribed to receive it, knowing that I do not celebrate Christmas?

It is permissible to receive free gifts from a store that offers them at certain times as a form of commercial promotion, unless the participant celebrates that day or takes it as an Eid. This is indicated by what was narrated from Ali ibn Abi Talib, may Allah be pleased with him, regarding his acceptance of the Nowruz gift, and that this is not considered assisting them in their rituals of disbelief. Similarly, benefiting from discounts during innovative Eids is permissible, as long as there is no celebration or assistance given towards it.