Jackonicko, Not everyone joins a golf club/ham-dram group/church/Lodge or whatever for their own benefit. I note your earliest comments have moderated throughout the thread and I consider some of the replies to them have been highly charged and wide of your professional mark.
I am a Mason, I have also spent 17 years in the RAF - not once (ever) have I found there to be a contradiction between the two. I have never been asked to give undue assistance (or any assistance) to fellow masons and have only known a handful throughout my time. I do not expect/look for/use my membership for advancement and I would be disgusted by anyone that did.
So why join? My family have been Masons for nearly 90 years from my grandfather down, of my 7 uncles, 7 are in my Lodge. Not everyone is in it for himself - or perhaps they are. Perhaps they wish to spend their time learning something and wishing to live by a code which they idealise. Perhaps they want to spend some of their time in the company of like-minded individuals (have a look in the bar on a Friday night). Perhaps there are things that mean more to people than their personal advancement at the expense of others.
I am not a saint, nor do I remotely suggest that I have the personal fortitude to live up to these ideals all of the time - but I am willing to try. If I don't want to tell you, Mr Blair, my Flt Cdr, or the official office for Mason Registration it's not because I'm trying to 'hide' something, it's because it is none of your, Mr Blair's or my Flt Cdr's business.
Please don't take offence at that but I am starting to get perplexed by the growing number of people wishing to know what everyone does, when and why - perhaps George Orwell had something when wrote 1984.