Presumably there’s a reasonableness factor built in (a la Feldman v. Google). It’s a future’s contract – you get the price everyone else is paying. I think they have an option that you don’t have to get it if the price goes up (on produce, for example). At least they did years ago when I used the delivery service.

What’s the alternative though? If the prices on the website are just estimates and the prices you’re charged don’t match the physical store, then what stops Safeway from declaring an emergency price increase and charging you $150 for each bottle of soda? At least having the prices be equal to the in-store prices provides a certain bound of reasonableness to the estimated prices.

I’d also be curious how pricing policies like this interact with laws like California B&P 12024.2 (or other state mispricing laws) which make it illegal to charge more than the posted price for goods.