There's nothing like taking a bat to a wasp's nest, is there?
First off, balls are not necessarily going farther. The balls that now go the farthest are now soft enough to be played by players who require a ball to have feel and spin. And by experimenting with core sizes and dimple patterns, manufacturers have found out how to have optimum launch angles off the driver with low spin speeds, a perfect combination for distance, especially when combined with firm, fast fairways (a big contributor to distance and something most everyone here would agree is desirable in a golf course). And amazingly, these same balls when struck with lower swing speeds (i.e. short irons) produce optimum launch angles with higher spin rates.
So, the OEMs are making better equipment, esp. when it comes to golf balls. The problem with all this R&D is the cost is passed on to the consumer. And one other note about higher costs on equipment is that there is one little secret the OEMs (esp. the publicly traded ones) won't and don't discuss, and that is that with the stock-holder mandated shorter product cycles come the planned-for markdowns to blow out "outdated" inventory. The manufacturers jack up the price originally of "new" product so they still have room to make their margins when they (inevitably) have to mark down the product 9-12 months later.