I cancelled Prime about a year ago - delivery sucks at my location with their logistics and I just don't want to deal with it. I still occasionally order some things that are hard to find elsewhere, I just ship it to an address where things won't be immediately stolen.
And after the huge "subscribe prime" interstitial with the tiny "not now" button, they still add prime to the order, not as a regular line-item, but as something you have to hunt around for to remove. They're cramming, just like telecom used to.
Amazon is awful if you have the temerity to fail to tithe them as they believe they are due. Fuck them.
Granted, Amazon has much less need for that endless stream of marketing email because they're already the de facto first choice shop. It's a lose-lose game if you're a conscious consumer and both want to support a non-Amazon monoculture for internet retail but also don't want to have to yet another drip feed of marketing email.
Ideally there'd be competition among email service providers to recognize the modern landscape of CAN-SPAM compliant but entirely unsolicited and unwanted email and provide user tools that aggressively bin non-transactional email and penalize senders that send 10 "transactional" emails for a single interaction ("here's your confirmation! here's a shipping update! here's another shipping update! are you satisfied with your purchase? leave a review!) as shadow marketing.
Either they're knowingly doing this for brand reinforcement reasons or are honestly clueless and don't recognize that a single email that links to a continuously-updated order status page is preferable. I figure mostly the former, but either way there are limited mechanisms to encourage vendors to make judicious use of email.