Imagine yourself at high seas, and you need a mahjong tile-set. You won´t get it. But you may get out some cards and use those instead. Even better, when sitting anywhere in the world and you desperately need a set for a playtest or review you´re going to make and NOBODY in the neighborhood or anywhere close has one, and buying a real one is too expensive (looking at you amazon with your 20+ bucks mahjong sets!) then this is a great alternative.
Seriously. Simple to make, good cutting margins and still a good look. We enjoyed using them and I´d definitely enjoy using or buying this again =)