I had originally meant for the meme to communicate Person A buying one $25 card for Person B and one $25 card for Person C and Persons B and C buying the same for each other and Person A simultaneously, which would be $25 * 2 * 3 = $150 spent.
However, I also figure a non-simultaneous gift exchange could occur, which engenders a couple of other scenarios:
Person A could buy one $25 card for Person B, which Person B re-gifts to Person C, who then re-re-gifts it back to Person A, which would be $25 spent.
Alternatively, Person A buys one $25 card for Person B, Person B buys one $25 card for Person C, and Person C buys one $25 card for Person A. Each person then re-gifts their card to the remaining person who has never owned the card. The three original cards are again re-gifted from their third owner back to their original owner. $25 * 3 = $75 spent.