Luxury Club on My Card, Panic at Payment

My roommate Russell saw my sister Marta give me a $20,000 membership card to the ice skating club.

She immediately came over and said, "We just finished exams. Let's go relax together."

I replied, "I don't have time recently. I need to prepare for my graduate school applications."

She pursed her lips and said:

"You just don't know how to enjoy yourself. If you're not going, I'm definitely going to have some fun."

I was a bit confused. A single visit to the ice skating club cost at least $500. She usually wouldn't even buy a $5 makeup sponge. Would she really spend money to go to the club?