Aaaaargh. Our ds's primary school were selling red noses in school for the first time ever this year. (There is a Sainsburys over the road so probably via them.)
We got away with buying one red nose between the 6 of us this year (4 children, dh and me) and 3 'donations' via school for non uniform. Oldest ds is in sixth form without uniform anyway so he doesn't need to pay.
Youngest, 8 yrs old, could go in non uniform, 'red if you have it' suggestion from school. Thought we'd put him in a red t-shirt with a skateboarding dinosaur that glows in the dark on the front but when checked last night it was for age 4-5. 
Now that's being a bad mummy. He is wearing a grey Transformers t-shirt with red sleeves, trim and part of the picture is red. Bought for oldest about 10 or 11 years ago. Can't be bothered to buy new red stuff when we can recycle old stuff that still looks good and had World Book Day just a week ago, it's not like any of the money for new clothes goes to Children in Need unless it's specific things. (And for WBD we got a penguin dressing up outfit from a charity shop for £3, bargain, which he wears all the time as he loves penguins. Win-win.)
So we forked out a grand total of £4.25 for the day. Any other donations will be our choice, not diminished to 65p per red nose. If we bought a red nose each we'd be paying £7.50, with a minimum of £3.90 going to charity. They get more money from a direct £5 donation, doing that we'd spend less and not have 6 red noses lying around. Better for the environment, we spend less, charity gets more. Win-win-win.
I think they need to re-evaluate the red noses. Waste of money, not good for the environment etc. Unfortunately the 65 pences per nose might not get donated any other way so they might not get as much raised.