Unusual Tyre wear?

Poor alignment. You may have hit a pot hole or something. I'd take it to a shop and have it fixed or the tyre will get even worse. Do not put a new tyre (or a tire) until repaired or the new one will wear unevenly also.

Ed is correct. On both my '07 Santa Fe's the original tires wore on the inside only. I had the dealer check the alignment and it was way off. So, new tires then a 4-wheel alignment and I'm cruising better.