People seem to be under the impression that companies are interested in making art or quality programs. They arent. By their nature, corporations are driven by profit, that is their legal obligation to shareholders. Some use quality and art to drive up game sales, but that is a business decision. If making rehashed games with themes from when people were 15 makes a buck because that audience is now 30 - they will make it.
A rehash has a built in market, and a new concept does not. One is like a mutual fund instead of a stock. Stocks can be risky. The coders and developers and maybe some management might have a "passion" for games - but at the end of the day they are not happy with making a 1$ profit at the end of the year - even though that is the definition of a successful product.
If all salaries are paid, and all expenses funded, and more was earned than put in - thats success. If more people got the message then nearly every product on the market would be better.