[lazerwalker]

I dunno if this is still true, but it used to be the case (10+ years ago?) that Costco's pricing model was transparently "charge X% over cost", with X constant over all items.

This meant some items at Costco were expensive relative to what you could find elsewhere on sale, but it also meant it was phenomenally useful to figure out what items other retails were making obscene amounts of profit on.

[pier25]

I live in Mexico and the Costco products I regularly buy have barely changed their price in years.