Here's the problem and the main reason why many of us that have thought of this idea previously have never followed through.
Taken quite by surpirse at this nasty welcome (and without taking a moment to think before speaking), I looked her dead in the eye and shot back "Want to bet?". Needless to say, this probably did not endear her to me.
She then said "We have your card and will give it to her. If she thinks there is a proiblem, she can call you." I'm sure she will.
As I left, I secretly hoped they'd get hacked that night. It would server her mean old ass right. After all, I am just here trying to help the ignorant stay safe - for free - no strings attached.
You gave them your business card, and showed them that they're vulnerable.
Now, if they're breached in anyway, there's gonna be a LEO knocking on your door, and you're gonna be hard pressed to prove that it wasn't you that did it. It's gonna take hiring an attorney.
Good luck, I hope something bad doesn't happen.