Why are there no botique car audio recievers?

I don't want to pay for a screen or cd player, just a decent sounding preamp with an aux in. Does such a thing exist?
It exists and you can still buy them on eBay and othe similar sites. Slightly older ones pre all the Star Wars designs and lights sound much better.
I agree with Dkarmeli, I don't know of any good ones currently on the market, but there are a few which have recently been discontinued which are very good.

Look at any of the following:

Pioneer - DEX-P99RS - this still may be available, but I'm not positive. I have one and it's fantastic.

Nakamichi CD700II - easily the best head unit I've ever heard and also own one. It's long discontinued however.

Macintosh MX-5000
Clarion DRZ-9255

Do a google search of "DIY mobile audio forum" and you will find the Audiogon of car audio.

Good luck.
If you are going to use something like an iPod for a source, you don't need to buy a head unit. You can plug it directly into an amp or crossover and use the iPods volume control.
I think you meant Bankrupt.
I believe that Naim supplies Rolls Royce and/or Bentley and both Lexicon and B&O OEM for a few brands like Hyundai and Audi. I'm not sure if any of this stuff is available in the aftermarket, tho.
google car audio tube preamp. there are some out there, like hss.
Burmester for Porsche, B&O for BMW, Mark Levinson for Lexus
I look forward to read some of the answers of this thread, good topic, cheers.