That's the point. Producing products more cheaply allow them to undercut their competition, increase the size of their market and make more money. The side benefit of costing the consumer less is of no concern to them, but it's a benefit realized just the same. Demonizing profits and the people that strive for them is a curious habit developed by all too many Americans. Prices of products do go down.
Technology reduces prices.
Riding your horse into town and back may have cost an entire day. Now, you can whip by the grocery store on the way home costing a tenth or less of the time. That's a savings realized by using a whole host of technologies, the most obvious of which is your car. A more obvious example is the price of computers. Prices may go up, but prices are not the same as costs.