Regarding HaHa Crabs

I was with my brother at Hougang Mall shopping and walking around when we saw an open tank placed on top of a cabinet. Inside the tank was some weird looking "homes" for this creature called the HaHa Crab, the base of the tank was filled with sand. There were even toys for the HaHa Crab to play with.

I read the sign beside the tank and felt quite amused. Is HaHa Crab a new fad like seamonkeys?
Apparently each HaHa Crab costs S$25, a big tank would set you by S$65 (correct me if i remembered wrongly.)

The shell of the HaHa Crab looks plastic to me... could this be Crab Abuse? O.o