I ordered some seeds last year from henryfields.com and was placed on a mailing list. I did not ask to be placed on it or set any checkbox on their site. Usually this is no problem as one may opt out after getting the first mailing. The problem is that I have followed the opt out link about four times, sent emails to the contact support address, and made a call to an actual person once, all with no result. I continue to get spam from them. I made the order LAST winter so they have had plenty of time to remove my address.
I really don't understand why some companies think that if they force you to get unrequested and unwanted email that you will continue as a customer. I will never order from them again or any of the other associated d/b/a's owned by the same company. I wont mention the name but it is easy to do a search. I don't know if the other d/b/a's have the same problem. All I can do now is plonk them and warn others about what they can expect if they order from them.
Just found a site that has feedback and rating from customers for gardening companies. Think I will put in my $0.02 next spam I get.