Some large companies even flagrantly violate the extremely lax rules that exist in the States. Guitar Center has infamously been sending me emails that are in direct violation of the one click unsubscribe regulations for almost a decade now. I can’t even sign in to the account to cancel the emails (which is in direct violation of the regulation- it is ambiguous on a lot of things but the one thing that it isn’t is that you aren’t supposed to be required to log in to opt out of email communications) because it was made with my dad’s email from 20 years ago yet I’m the recipient of the spam.
I did report them; but of course nothing must have happened because they are still doing it.
The LinkedIn way.
In the UK, it appears to be illegal to even develop a website or app that "instigates" a user to invite their friends to that website or app. This includes pre-filling an email that they send their friends. So, any sort of viral mechanism that people on YCombinator and Hacker News have used to grow their websites with "hockey stick growth" is illegal in the UK since 2020:
https://dpnetwork.org.uk/opinion/refer-a-friend-viral-market...
“An online retailer operates a ‘refer a friend’ scheme where individuals are given 10% off their orders if they participate. The individual provides their own name and email address and the retailer automatically generates an email containing its marketing for the individual to send to their friends and family. The retailer is instigating the direct marketing therefore they have responsibility for complying with the PECR rules. Because the retailer does not have the consent of the friends and family these emails breach PECR.”
That's right, the UK is policing what businesses can provide for people to privately send their own friends! There is simply no easy way for your users to legally invite their own friends to your site, so it can never reach critical mass. This would probably destroy the business model of 99% of YCombinator's B2C companies, Facebook, Twitter, and any website with "invite a friend to do X with you" functionality.
Referring friends and family by sending emails on your own? Who the fuck does that since ~2010? Ever heard of social media and instant messengers?
Social media MAY be an exception, but that's because people are already used to receiving a ton of spam on it, so your "viral post" will be ineffective to begin with, and probably filtered by Facebook and not shown to most people at all. Enjoy.
All the original social platforms such as Facebook and Twitter used ways to invite others by email (famously in Harvard etc.) So now they are burning the bridges behind them and no one can do it anymore.
And then there's those online stores that cover the entire page in a popup that you can get a 20% discount code if you give your email. Technically I've opted into their marketing. But I always just use the coupon and then report the email as spam without bothering to unsubscribe.
A few times I've had unsubscribe links absent or not working for whatever reason and done that and a human's replied and sorted it out.
(An attacker used the paypal guest account feature and used my IBAN [european bank account number] and tried to hide the mail within those hundreds of mails. They were successful for some days, until the purchase showed up on my bank account)