Bicycling Magazine Subscription

I received a free issue for this magazine that was offered over six months ago on an Internet site have I long forgotten.
I didn't like the magazine content, although I am a biker, and chose not to subscribe at that time and forgot about it.
Since receiving the free issue I have moved twice.
Now that my mail has caught up to me I just received a collection agency notice on behalf of Bicycling Magazine in the mail for $19.97 for a subscription I never ordered. Obviously they assumed that receiving the free issue somehow obligated to pay for a years subscription.
Although I will be dealing with this magazine through other channels I thought it best to have reviewers be aware of this tactic being used by the magazine at least to me.
Buyer beware (although I wasn't even a buyer)
My epinion is avoid them at all costs if this is how they treat potential customers.