In reply to Christine:
Have you had a look at the policy details for the BMC insurance though? I've had a flick through, and the amount paid on death is £5000 (based on a Rock climbing policy I took out recently). Thats in all likelyhood not enough to cover a mortgage should you die. The BMC insurance is basically travel and medical insurance, its not really life insurance.
Insurance companies load premiums for rock climbers. Much as we would wish to deny it, you are more likely to make a claim if you climb than if you don't, so the price goes up - thats the way it works. They have the statistics to back it up, I'm afraid the loading isn't done simply to penalise, it is an attempt to mitigate the increased chance they have of having to pay out. Its not really prejudice, its simply the theory behind how life insurance pricing works - you try and split people into small groups of similar risk and price the premiums appropriately. If you had one blanket premium rate regardless of hobbies etc then you would end up having everyone else pay more to subsidise the people who engage in more risky sports or who are generally more unhealthy (or, by logical extension, if you only charged a single rate the young would subsidise the old).
I'm impressed that you had to rant down the phone. We (I work for a UK insurance company in life insurance pricing) would generally state why the premium had increased on the terms and conditions, and I had previously imagined everyone else does as well.
Theres a variety of things that can make it better. Being a BMC member is a good sign, as is having climbed a certain number of years, these can reduce or eliminate the premium loading. Climbing outside the UK probably generally increases the premium (an interesting thing for those who only ever go bolt clipping, which is probably far safer than scottish winter for example which would obviously fall into the UK geographical banding), but then if you can try and speak to whoever is actually underwriting your case and explain to them what sort of thing you are doing you might be able to get a better deal. However, I imagine that Via Ferratae will probably still be viewed as increased risk since they get you up into proper mountains with associated rockfall, weather etc risks.
AJM