Why don't amplifier Companies use high end fuses?


My equipment - Raven Integrated Reflection MK2 tube amp 58wpc. / Lumin A-1 DAC Streamer / Synology NAS / Isotex Aquarius Power Conditioner / Furutech Rhodium Plug / Sonus Faber Amati Homage Tradition speakers.  

I have read thousands of comments on upgraded fuses improving the performance of sound.  I am very open minded but not sold either way.  So, the question I have is....if fuses were so important, than why don't Amplifier companies all install them as OEM equipment?  To me, if they are as good as people say, that would provide companies who use them a competitive advantage?  

Every High End Audio store I go to in Phoenix have told me it does not make a difference and is a waste of money.  For the record, I have fuses purchased at an automotive store for under $10 and I think my sound is awesome.  The Company that built my amp tested the Synergistic Fuses and he emphatically said there was no difference.  

If I were to try a fuse for fun, given my equipment, what would your recommendation be to try?  
willgolf
HA HA HA. Why don't they use better resistors, capacitors, chokes or transformers, chassis metal thickness, feet, etc. Cost to price ratio? I think those would make bigger improvements than some fuses IMO. Why not just use a copper bar?
Any designer worth it's salt don't just assembled a combination of most expensive parts but a combination that meets a goal. 

I understand every time a DIY replace a part, WOW!!!  Unbelievable improvement, more organic, resolving ...
So you don’t think a designer ever thinks, "I wish I could spec XXX, but just too pricey"? C’mon. Why are there "SE" editions?

Dave
So you don’t think a designer ever thinks, "I wish I could spec XXX, but just too pricey"? C’mon. Why are there "SE" editions?
Good business sense??   They trickle out changes whether SE or new models to generate interest.  So you propose companies offer one product cycle and close the doors?  
Nice dodge. The point was that designers think about how to design their best sound into a component within a certain price range and given more $$ would choose to spec a better traditional component that they feel more confident in than a fuse.

Dave
Components in well designed amps are selected for their sound quality and reliability, often from actual listening to the differences between them, and designers clearly understand the logical design parameters of the components. "Special" fuses have no actual design benefits or any logical explanation anywhere as to how they improve anything (thousands of comments…still no "how or why"), and trusted brands like Littelfuse products are extremely reliable, properly rated, and generally work perfectly for a few bucks each. That’s why.