It's not just you -- CreditKarma checked my credit monthly for a long time in 2019-2020, until I changed addresses. I have never used a CK product. Obviously it's too late now to do anything about it but the existence of this site and the fact that Equifax is still in business makes me incredibly irritated.
A lot of consumer banking products have CreditKarma integration by default as a perk or for your "convenience". Digging through one of my checking account's apps shows that there are credit score previews with a button to activate CreditKarma and receive detailed credit breakdowns. I'm guessing that credit preview is provided by CK and not my bank, given the CK branding.
