If it’s so pitiful I’m sure the BOA would be happy for you to have your £15 back in return for your membership card.
Alternatively you could be a bit more constructive and as a long term internet user offer to help the Association in setting up something that may be more suitable?
Don’t forget that the BOA is only run by half a dozen or so members, the majority of whom all have full time jobs etc and run the Association by giving up their valuable free time.
Whilst your comments may have some merit you do appear to lack tact and diplomacy.