Maybe it is just my experience, but individual tracking (which is the sort of tracking under consideration here) does not seem to help, let alone be necessary. I do not think I have ever found something of interest in things that have been pushed at me, and the only thing that helps navigating a massive catalog is more extensive-in-scope and discriminating search capabilities.

To add to this, what if the vending machine was able to dispense 1000 things? And let's say that you are diabetic? Wouldn't it be nice if the sugar-free treats were easy for you to find? And the organic stuff easier for those seeking them to find? Etc. etc.

Somewhere there must be an intelligent balance.

That's an argument for good search and discoverability - a sugar-free aisle.

Amazon could be that machine, if we could rely on them to (at the customer's option) properly delete the customer's credit card number and delivery address when the package is delivered.

> Somewhere there must be an intelligent balance

In practice though this is mostly biased towards the revenue of the company selling the goods, not towards your health requirements.

It's in the interests of the company to align those however - so these don't conflict. If your customer is healthier and lives longer because of your service, that is beneficial to both of you.

Good health of the customers benefits competitors too, so it's a type of commons. By the Tragedy of the Commons, it's in the company's interests to damage the health of their customers for short term profit. If they don't then a competitor will.

How did diabetics even manage to buy sugar-free snacks before Amazon's recommendation engine?

Thank god for Amazon profiling them, they must have been starving before.