I've had a thought about this problem of weight for the past couple of days, and frankly, I suspect its a mixture of 'perfection being the enemy of the good', what people know and can reasonably get hold of, and cost.
From the schools point of view, its going to be Vango. If you've only so much cash to buy tents fo X number of kids to last X number of years, then Vango gives you the biggest bang for your buck. They've got to be reasonably robust and easy to put up (because they are all 15 and have never put up a tent in their life...), and you can get a Vango Banshee for £99. Yes, you could go lighter, but somethings go to give. I'm sure at Eton they have Hilleberg - in fact at Eton they probably have ones like in Harry Potter which fold down to nothing and are made by goblins, but at the average state school, if they can afford it at all, its not going to be that light. It might not be perfect, but its either having 6 tents or two tents, what would you chose?
The reason they have 65L rucksacks is twofold. Firstly, if your borrowing a sack for a festival, trip, etc, what size will proably be available? Its probably a 65L (because its the most popular size), which was bought by someone for DoE, a festival, camping trip with work, travelling twenty years ago, etc. I know the size of the one in my loft - its a 65L, and I bet most of the people on this site have pretty much the same thing.
Why cant you have a smaller rucksack? You can, but think about whats going to go in it. If its a sleeping bag, and you ask to borrow one, its almost certainly going to be cheapy synthetic 2-3 seans bag bought from Argos, Blacks, local surplus place, etc for much the same event as above. Hopefully its going to keep them warm, but its going to be big. Cos its big, you going to need a big bag to carry it in...if you have someone with a lovely down bag, your golden. But would they lend it to you - I know I probably wouldn't.
Imagine you know nothing about hiking equipment, etc. You look at that list, and think -' how much?!' You know your kid isn't going to use the bag that much, so your after decent value for money. You dont want them getting cold (quite right - nothing is more miserable), and you dont want to spend a fortune. The Vango ones are £45. Yes, they are huge and heavy, but try to be the saleman who points out that the lighter but equally warm bag is about £140. Good luck with that. The same goes for the sack - you can point out that an Osprey 46 with a lightweight bag inside will be much easier to carry, but your talking at least 200 notes just for those two items. Again, thats not going to fly for most people.
The list is a guide, and hopefully they'll get good advice from leaders, but again, you have to put down stuff which is reasonably available, at say Blacks, Cotswold and Go Outdoors. It can't be too pricey either, so Vango tends to get featured on the list. Could you save money and weight? Yes. I'd chuck out the survival bag, I'm sure they've already got fleeces, and I'd head down to Lidl, Aldi or TKMaxx for socks, gloves, baselayers, etc. Actually I get my Sigg's from TKMaxx. And Alpkit for headtorches (the Gamma is basically the same as the Lifesystems one, but £10 cheaper, and their new ones are cheaper still), mats and drybags. That might give them a bit of extra cash for a good deal on a sleeping bag.
Although I'm not sure I'd spend out on a DoE 'tool', I can see that having sharp knives and 15 old boys do not mix!
Much as we would like them all to carry less stuff, its hard to do that without spending more (although there is some swapping around to be done), so the best you can hope for is to get the best value they can, to be able to pack down as small as possible. I suspect that the Berghaus Torridon was the best compromise you could have in terms of price to weight, and hopefully better lighter stuff can be purchased to ease the pain of carrying everything!
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