Yes, it has a lot of advantages, for the relatively small price. I pay 50 Euro for 6 month delivery service, that goes monday to saturday from 9am to 10pm (you can pick a 2 hour window inside this time frame). Usually I order once a week, so its 2 Euro per delivery, give or take. Which is about $2 .20 - that is the best deal ever, as it saves me at least an hour of time, searching around in the supermarket, standing in a queue at the till among coughing and sneezing people, and then hauling the stuff home somehow.
But I can see why they hesitate to implement such a service in your area. Its of course much more economic to do this in a densely populated area. I mean, even here I wonder how they make this work. Even a poorly paid delivery driver here gets about 12 to 14 Euro per hour, plus the cost for the vehicle (a small truck with a refrigerated box body). So he would have to do at least 8 or 9 deliveries per hour just to break even - incuding the driving time and all. That seems hardly possible, unless there is a customer in every second house or so. And no - the goods are not more expensive than in an average supermarket.