This is intentional. Email verification is friction, so it gives users a chance to reconsider whether their purchase is really necessary. This is bad for business, because they’d prefer if you were impulsive.
Also, people usually type their emails correctly, especially these days with auto-fill. So not sending confirmation emails is optimizing for the happy path.
Not just talking about purchases. I receive transaction details with bank numbers for wire transfers around the world. It’s ridiculous.
I was once even sent all of the legal proceedings for a court case by a lawyer who was sent to the wrong address.