Instacart has network effects that make

Instacart is hardest to dislodge where it becomes part of a grocer’s operating system, not just another delivery app. The durable loop is that more consumer demand brings more retailers and brands, then those retailers adopt Instacart software for storefronts, fulfillment, ads, smart carts, and order management, which makes switching costs higher because leaving means replacing both demand and tooling at once.

• Instacart won by using existing grocery stores as infrastructure instead of owning inventory. That let it aggregate enough orders to survive a market where picking and delivery are expensive, then spread that demand across many chains after Amazon bought Whole Foods in 2017 and forced other grocers to look for a counterweight.
  1 sacra 3 instacart 6 aboutamazon
• Uber could reuse couriers and restaurant app traffic to enter grocery fast, but interviews show that partnership led grocery tends to be weaker at habit formation and retention. Instacart goes deeper by plugging into retailer workflows, while Uber mainly adds grocery as another catalog inside a broader delivery app.
  1 sacra 4 sacra 7 uber
• The best comparison is Weee!, which captures 40 to 50% of a household’s grocery budget through owned assortment and direct sourcing, versus roughly 5 to 6% for Instacart. That shows Instacart’s moat is not exclusive grocery demand, it is its shared utility role across thousands of stores, brands, and shopping workflows.
  5 sacra 2 sacra

The next phase is deeper infrastructure lock in. As more grocers use Instacart for ads, in store commerce, AI tools, and white label storefronts, competition shifts from winning a delivery order to replacing a full stack of retail software and demand generation. That makes the business look less like a thin margin marketplace and more like grocery infrastructure.