What is the ruling on points gained from purchasing food items, which are then granted as a gift or enable purchasing without payment?

What the institution grants to its workers falls under the category of a ju'alah (reward/stipend), and it is permissible, as evidenced by the verse: "And for he who brings it [the lost object] is a camel's load, and I am responsible for it." So, if the worker completes the agreed-upon task, he is entitled to the promised gift or item.