Deal rules?
Am I right in thinking that some companies restrict deals on their hardware? I'm thinking of companies like Apple and Sonos - both of which are not discounted by the normal web sites or indeed shop (a salesman in my local shop told me that the Sonos 3 promotion was organised by Sonos rather than any individual shop) as well as other industries (such as Desser who make conservtory furniture).
I assume that such companies will stop supplying shops that discount their hardware to try and keep the quality impression of their products?
As Sony back in the day
Thanks Ben, the Spartans would be proud of you (actually, I wasn't expecting any more, just confirmation)! 
rgds
As Sony back in the day
Ahh yes, I'd forgotten that. My first colour TV was a Sony (for my Spectrum) and having done lots of legwork I discovered that the model I was looking for was the same price everywhere. It didn't occur to me at the time that it was controlled by Sony - I assumed that it was shops feeling that they didn't need to discount to shift boxes.
Correct.
HiFi / A/V / Bedroom