In reply to WillBroad:
Frames may come out of the same mould, but not only will the lays be different, the actual carbon-fibre (sheets) used can also differ significantly in terms of the fibre modulus (strength). There are also different resins to bind everything together.
However, you do pay over the odds for a branded bike - after all a brand has to support their development costs (such as the moulds themselves which the factories often use for their smaller customers and own unbranded frames, but usually only after the mould is no longer current for the originator brand), and they also have their very significant marketing costs (glossy ads, pro teams etc).
There are not that many factories making top-end cf bikes - maybe half a dozen to a dozen, so you will see many different brands being made by the one factory. Smaller brands use non-current moulds developed by major brands, although I am not sure how many bikes can be cast in the one set of moulds. They do have a finite life-span.
It is relatively straight forward for anyone to source suppliers/manufacturers of bike frames and components and set up their own brand - all they need is the start up capital and a distribution channel.