Must say I'm surprised.
You shouldn't be.
Bear in mind that the member demographics of CBF are weighted towards England and Wales, with a lesser number of members from Scotland and in the vote, Scotland and Northern Ireland voted heavily in favour of remain and England and Wales the opposite.
Young people also voted in favour of remaining, 75% of 18-24yr olds and in the slightly older bracket, 56% of 25-49yr olds also voted to remain. Those who are 50-64yrs old voted to leave with only 44% voting to remain and the over 65's voted even more heavily to leave, only 39% of those wishing to remain.
I'm not going to say that the majority of CBF members are old farts, but I'd hazard a guess that most fall in to the latter two age brackets.
Ironically, it would appear that the Remain campaigns forecast regarding the economy if we voted to leave, as in plummeting sterling, inflation on the up and a very shaky economy for the foreseeable future have been a lot more accurate than the Leave campaigns promises of extra funding for the NHS, reduction of immigration etc etc.
JF