Probably because you post in all uppercase, which for decades on the Internet is deemed shouting at the recipient. 🤨
You don't have to do business with the source of your junk email, as email lists are readily available for sale on the dark web, even associated with special categories of the owners product interest and geo-location. Online privacy and privacy policies are a joke when employees covertly sell these lists for profit, or businesses share them with their shady partner firms, or privacy information is stolen from vendors with really poor site security that can be exploited by professional hackers and foreign actors.
One option is to either change your ISP email provider, or choose another email user id that you exclusively use for online purchases or other activity. Then create a Mail rule that filters on that specific "throw-away" email address and sends it to the Trash. A mail rule can look for any email sent to a specific user and just move that to the Trash. That way, nothing lands in your inbox.