>A company with 60% market share gobbles up a company with 25% market share.

Can you be more precise about what percentage of what market? I think you are conflating restaurant delivery with grocery delivery. How would instacart have 25% market share and door dash have 60% and Uber eats have 26% and Grub hub have 8%? Doesn't add up because you are mixing markets.

Instacart doesnt event have 25% of grocery delivery. That was 5 years ago. Instacart's market share is declining - Im seeing 18%. Doordash offered around $50B in 2021 now offering $17B.

The grocery stores themselves are actually the major competitors on grocery delivery and they cant serve other small business like the independent services can.

I have to say I'm surprised GrubHub is so small.. I thought they were basically a clear number two