As a counterpoint, I've never had a positive experience with Instacart. Whenever an item is missing (and sometimes I suspect they just can't find the item in store - one time they told me Whole Foods had no parmesan cheese at all), there is a frustrating back-and-forth texting frenzy to decide whether or not you want something else. Not only is it not what you want, it inevitably costs more, and a typical order will have something like a dozen texts from the shopper. In addition to this, the markups are way too high in my opinion. And since I'm not in the store, I never know what's on sale and can never take advantage of it.

After about a half dozen tries I gave up on Instacart. It was so much worse than just going to the store myself.