I use individual emails for every company I deal with.
So if I'm signing up for one service, I know exactly what email I gave them, and if I get spam, I know exactly where that address came from. And if I don't "create" an address for a company, there's no way to contact me except on a generic account (e.g. my name) which I never give out.
Then I got an email selling furniture for schools (which was quite clearly a new company spamming to drum up business). I wondered how they had got hold of my address as it wasn't anything I'd ever signed up for. Turned out that the email address they were using was the one I had given RM (remember them?). And they seemed to be an entirely unrelated company.
I unsubscribed, and they still spammed me relentlessly, so I called them up. It took a while for them to get what I meant, and then got to someone who I could actually confront, who was instantly red-faced and sheepish.
Turned out that their director was a former employee of RM, who had recently left to set up a company of their own, and in the process had stolen the entire RM address book and used it to spam all their customers.
To say they were shocked I'd managed to expose this in the matter of hours of being sent an email, that they then panicked trying to undo it all, and that they promised rather comprehensively I would never get another email from them ever again (that was my deal that I offered... I don't care where you got the address from, but if I receive a single further email from you, there'll be a nice message winging its way to RM's data protection department) is an understatement. They soiled themselves.
I never did get another email, nor buy anything from them. And I kind of judge RM that their customer address database / CRM / whatever lets you just exfiltrate the entire contents like that.
But it happens all the time, and it just shouldn't be possible. Why does anyone working at RM (or indeed anywhere) need to see my email address, or be able to export the entire address book to a third party device?