It's not actually that stable of an investment vehicle, sure price have generally been going up over the past ten years, but if you bought gold in around 2012, you would have lost money if you where not able to hold on to it for another eight to ten years.

Personally I think the prices might be to high and a drop is coming. To keep the market moving someone is now trying to create a new market segment and is attempting to pull in new customers, apparently via Costco. This is either to prevent a slump in sales or to offload gold holdings before the price starts dropping.