Oh No, I must politely disagree. They are most definitely NOT a scam. They are a top notch and reputable IOP.
I have always used cash and have not had a problem.
If you look at all of the threads on this particular IOP there is overwhelming positive experiences with them, mine included. I'm sorry you are not having good luck, perhaps the email you are using is incorrect. They've always responded to my inquires in a timely fashion.