Seeing a fortune teller is only 'bad' if you do one of two things. The first thing is believing the religious fanatics who throw bible verses at you and tell you you'll go to hell if you do that stuff. The second thing is believing that the fortune teller has some sort of genuine supernatural ability and is really seeing into your future.
Most fortune tellers are NOT frauds. They have signs up on their wall and in their ads that say "for entertainment purposes only" and some of them will even have their customers sign a disclaimer saying that very thing. They're professional entertainers, and some of them are extremely good at what they do. When you pay a fortune teller, you're paying for the entertainment value. Go ahead and enjoy it.
Fortune telling is a mixture of art and science (I know several of them professionally), and takes years to learn and perfect. The only frauds are the ones that tell you they really are connected to the 'other side' in some way, and those ones are easy to spot and easier to bust. But when a fortune teller says the entertainment-only thing in writing, you don't have to bust anybody. They're being honest when they say that, and you can't bust honesty.
Now that you know the real story behind them (look up cold reading if you want more info), you tell me if it's bad luck or not.