I use such deliveries occasionally (Glovo, mostly) for items that are maybe a 30m+ walk away, and that I forgot to order. For example, I'm after work, I realize I'm out of cat food, I'm too tired to spend 1h+ walking, and taking a cab is as expensive (it also happens that public transport between this particular store and my home is really bad). So, I order a bag of cat food off Glovo and get it delivered 30m-1h later. If I ordered from the store it would arrive 2-4 days later, and I can't find the brand my cats eat anywhere closer.

Now, this is just a small convenience - it won't change my life if the service goes away, and I don't use it often at all, but it's nice to have. I don't think they have any chance of making the money back on such order though.