Because with your real name, people can easily identify your address, your place of employment etc. This would open people up for a barrage of things. In my case, some people take offense to the replies I give on certain campground issues. Those people would like nothing more than to be able to post some bad reviews about my parks, even though they have never set foot in them. Other people post viewpoints that might invoke political, religous or other special interest responses. I don't think too many participants on this forum would want the members of that crazy church in Kansas that protests military funerals to use their personal information to badger them if they posted their support for our fine troops. And if you posted you were interested in buying an RV, I don't think you would want your phone ringing off the hook with solicitations to sell.