Why is this better than that?

The Nagasawa on sale elsewhere in this forum looks identical to my Lotus conversion. The only difference being the colour scheme and the apparent £1000 price tag. Why does a (in my eyes) pretty standard bike hold such great value? I get the same impression when I see a Bob Jackson. Why do you guys pay so much for these frames?

Outside of any demonstrable and measurable benefits of a better brand - basic human psychology plays a large part, but of course you know this.