You’re wrong. Sorry about it.

In most jurisdictions anyone would want to live in, a handshake deal is as good as a contract.

Additionally, and again in any jurisdiction anyone would want to live in, when you purchase a durable good you’re entering into a contract with the seller and / or the manufacturer with regard to the advertised claims of the product and any warranted considerations.

Also, consumer items usually come with some guarantees, for example that your baby spinach didn’t kill you or result in harm to a gestating foetus, and so on and so forth.