I actually think that carrier imposed charges should qualify as eligible spend towards nTPs. I don't see that this sort of spend is any different to, say, paying for seat selection which is a qualifying spend. As carrier imposed charges are purely a fee imposed by BA to contribute towards the cost of putting your bum in a seat I simply don't understand why this spend doesn't contribute towards nTPs given that this is now a spend based system - you're spending money that contributes to BA's bottom line.
I think this is cakeism on behalf of BA and is one of the areas that they could reconsider when making these harsh BAC changes.
Note I'm not advocating that taxes/government imposed charges should contribute - although I believe some people have said that for ease of application, all charges on a ticket i.e. the total transaction cost should be the determinant of now many nTPs are awarded.