If I'm a business owner and I see that Shopify knows my business as well as I do, I start to ask questions. What's stopping them from figuring out what the marg

If I'm a business owner and I see that Shopify knows my business as well as I do, I start to ask questions. What's stopping them from figuring out what the margins are in each of these businesses and starting up a competitive business with a few business that have the highest margins? A diversification of cash flows streams never hurt anyone right? ( Yeah I'm looking at you Amazon)