The S&P at 1800 by December?

One of the trades picked up on my options screener today is volume of 6300 December SPX 1800 calls that have traded today. These mostly went off at $1.30 or near the offer. The spread is outrageous with a bid of 85 cents and an offer of $1.35. Imagine, the S&P rising nearly 300 points more by the end of the year. Who knows exactly what that's all about - some sort of swap, or hedging? It's just way out there.