Costco isn't a grocery store, it's a retail bulk warehouse. Shopping daily at it makes little sense, nor does shopping daily at a small store for items at a higher price for most incomes. Good urban design would place it further away as it's a destination shopping trip intended less frequently. Public transportation would have more storage space for bags and either a public or store delivery service would get larger items home.

You should be hoping that Costco stays in business and large every day grocery stores (Kroger, Target Grocery, etc.) don't last.