Sign in with your Adobe ID. Change your credit card # to something that does not work.
A bit strong calling it a 'scam' I think. That is just normal billing. Mine is monthly actually though I have heard you can select an annual option. Or am I missing something? Why can you not just uninstall it? Call Adobe and tell them you want to cancel. I have called with a couple of issues I had and both times received quick, polite and thorough assistance.
Curious what your issue with Lightroom is? There is a learning curve and it is not for casual users in my opinion but it is about the best out there at what it does. Of course if you don't need Lightroom or Photoshop then $10 a month will buy you a coffee every week.