I feel a little faint
I think that by the time you have driven around, like most of us do to get all our little bits and bobs, £30 for 100 is nothing.
Who hasn't driven miles to get a couple of £1 fittings?, plus the time involved. Twenty or thirty mile round trip will knock the price of those couple of fittings to most probably £3 or £4 each.
If you look at it realistically, most model boats have cost double what you think, when you add up fuel costs and time wasted on those little unsuccessful forays to get the parts we must have now, even when the boat is six months from finishing, when it could have been done a lot more efficiently if you were willing to pick up a phone and wait a couple of days for postage. How many times have you been to a show, most probably driven a few hundred miles, paid for entry, thinking you can pick up just what you want, and find you buy almost naff all, and what you were after wasn't there anyway. Ok if you are really interested in looking at almost the same models and displays year after year, but a very inefficient and expensive way of getting fittings.
By making them yourself, if you aren't very good at it, you tend to get a 'home made look', buy from the professionals, you usually end up with a professional looking finish.
I have seen some fabulous boats ruined, because of the 'well it would have cost me £10 extra , so I made it out of a toothpaste tube and a lollipop stick' attitude, and it looked like it was made out of a lollipop stick and toothpaste tube (just an example by the way).
You might say that this is the wrong attitude, a lot of people can't afford to spend a lot of money on their models. There is nothing anyone can do about that, if you ain't got it, you can't buy it. But if you want a good looking model and can't do a professional job yourself, you gotta pay. I am not getting at the people who can't afford the bits, but this is the real world, good or bad, that is just the way it is.
Myself, having all the machinery, I would make a lot of special fittings myself, but a lot of the time it just isn't worth the time and effort trying to make it yourself, if it was available from retail sources.
John