Yeah, they are a "wherehouse" store, where you buy things in bulk. It's where i buy my Rogaine, that's where the "Kirkland" brand comes from, it's the Costco brand. There is Kirkland dishwashing liquid, Kirkland toilet tissue, etc, along with the normal brands. The Kirkland brand of anything is usually a bit cheaper than the others. Pretty much everything you buy at Costco comes in huge amounts....You can't buy 4 rolls of toilet tissue, you buy 50 rolls at a discount, for example.
At their stores (at least around here), you can only buy Kirkland Rogaine in packs of 4 bottles, but it only costs around $18 total.