There are many reason for using an alias, one well known reason is Google.

try it for yourself. Google some of your user names on TER and you will find out a whole lot more info that you need to find out.

If you google BeefEater500 and/or his previous user names you will find very interesting posts, even some theories, some conspiracies and more!

I much rather be behind some theory as to who I am based on some math and some postings. Google has not build a search for that! I paid the price for not being careful.