This is because any company that has the potential for creating recurring subscriptions can do so to anyone at any time with nothing but an account number.
There is no pre-verification of authorization whatsoever. The only thing you can do is continuously monitor your bank statements and dispute the charges when you see something turn up, then hope for the best.
This system is croocked by design. Most people can't even believe it is this way , but presentations by budding fintech to small companies tout this 'feature' as the greatest thing since sliced bread.