Paraskevidekatriaphobia

Today is Friday the 13th. I guess it should sound like just another day for most of us. To some others it might remind them about the series of movies that came by this name. But imagine this, about 21 million people in the US alone are superstitious about this combination of the day and the date (Source).

Thinking again, atleast they are superstitious only about a combination takes comes few times a year. Compare the same with our superstitions wherein we are not supposed to cut our nails on a Friday, not shave on particular days of the week or after the sunset, not lie-down at 6:00pm etc. Well, we do have a big set of things to be followed without reasoning, and believe me; I have been following them religiously all these years. Sometimes we follow things because we have been brought-up that way. In my case, I also feel that there might be some reason behind all these things that is just not figured till now. Some guys term me as rigid, but frankly, I haven't got any reason to change. When I am following things that aren't going to affect me or anyone else in a negative way, why should I change? Atleast I don't restrict myself to the doors of my house because today's date corresponds to the number of people who were present in the last supper and today's day corresponds to the day when Eve tempted Adam to get the apple.
Btw, when it is a "Good Friday", the last day of the week, the combination that signals the day before the second Saturday of the month (which is a holiday in many Saturday-working offices), why should one feel bad about the 13th of Friday?