Fair question, and the right one to ask any top up service. Some services get their prices in ways that put your account at risk, which is why players get banned and purchases get reversed. Packsify does not touch any of that.
We buy official Apple and Google gift cards at volume. Your packs are then bought inside your account through the official store, at the normal store price, exactly like any other in-app purchase. The game company gets paid as usual.
Our price advantage comes from how we source the credit and from regional pricing differences, never from anything that affects your account standing.
That is why after 5+ years we have zero bans from our method.