I can't see a problem with the Facebook bit of this, or even the use of the logo. 
It is not using it for business purposes, if anything it may help other people find the club, so put the logo back!! 
 
 
As far as £27 goes, that just about covers the cost of magazine and website, and we havent raised the price in 3 years now.
Check out the price of other car clubs.
Also remember what a car club is for. It is not just a forum. Back when the club set up there was no forum, it was the magazine alone. 
Most insurers insist on club membership to obtain classic insurance and discounts. I bet the saving on that alone is more than £27.
I think that the insurers want you to be a CLUB member, not a forum user? I may be wrong but do Rods and Sods as a free forum get insurance discount? 
Clubs also need to be a club in order to get DVLA recognition for age related plates etc. 
How many members have saved their £205 per year road tax because their vehicle is now tax exempt thanks to a letter from the club? 
How many new friends have you made through the club? 
Would you trust people as much that you met on facebook as through the club? 
I am not knocking the forum, in this day and age it is probably the most valuable resource we have, for its speed of information transfer, friendliness, and all the other benefits, but the club is more than just a forum and maybe that gets forgotten sometimes. 
If we went internet only, it may reduce costs, but I suspect would also alienate some members who do not use the forum. 
I do not know the answer to this as regards the way forward with the club.
I have been here a long time (too long some may say!) and enjoy what the club is and am proud to have been part of making it what it is. 
I have no problem with people leaving either, if you don't own the car anymore then that link is gone, and there may not be a need for being a member. Vote with your feet. It's not like the club has upset it's entire membership, it s just that one person (Simon, Dave or Tony for instance) don't feel the need to renew. 
I was a Triumph club member for over 20 years but let my membership lapse because I wasnt using the car. I still have it, just hasnt turned a wheel since 1997. That club didnt fail, more people have joined since and it still runs as it did. 
Some people leave and then come back after a year or two, maybe just because other things are going on, the car is off the road or whatever.
I think there is room for facebook for those that want to use it, it is not an alternative to the club, it is a different thing. The two can exist together IMHO. 
Back to my welding now, I have said far too much for one cup of coffee .