Sandstorm isn't a good move in general, spending a turn to throw out some residual damage and a chance of an opponent missing is worse than just killing them with a better move. Yeah, it's a waste of an ability, but a small handful of Pokemon around Gen 3-4 didn't have a useful ability yet.
If you really want to use it, catch a Hippopotas.
If you were wondering about using it against others, considering Tyranitar and Hippopowdon are so common in DPP's metagame and Garchomp's ridiculous stats... Trust me, Garchomp was banished to Ubers for a reason, it's disgustingly good even without sand.