groundhand makes a good point but I think that the reason we notice these charges and ask about them is down to the fact that the billing structure is new.
Some of us have been paxing for [pause to count ...] 42 years
and had become used to the all-in charge so the new system can seem strange and irritating. I'm sure that those who have been paxing for (say) five years will consider the current way of doing things as normal, as indeed it is.
BUT the biggest source of irritation is that there is no standard schedule of charges, eventhough the charges are supposed to be standard! The fact that carriers blatantly expand T/F/C to include whatever they can get away with strikes a bad note. I understand that carriers will add in what it can and have no argument with that - but they should add that into their basic fee. Inflating 'tax' makes cross-comparison more difficult (which is what they want) and leaves you with a feeling of being ripped off. Simple example, some months ago I was looking at BA and they had the word 'insurance' there. We all know that BA will be paying significant amounts of insurance across all of it's business [can you insurance against the CEO making a staggering b@@ls up?] and so calculate that along with paying for the a/c and buildings. They probably put 'insurance' in so that we will think it is related to 'the war on Terror'
and they have got another Fiver. Again - no problem but it is disingenuous to add it in this way.
Whilst some folks relish change, overall, humans are creatures of habit. My thanks to
Hartington for the link to the codes list.