just playing devils advocate but going above and beyound costs money. Someone has to foot the bill for the bells and whistles and some might see this as taking advantage of the customer. Putting specification grade receptacles in a residential application would be viewed by many as a total waste of money and charging a customer for this item as taking advantage. I could sell this as "quality"to the customer but my techs would not view it that way and if they see my company value as one of ripping off the customer then if they do not quit I now have a serious employee problem because if they stay they have accepted that value as OK because they possess that same value.
Spec grade for a new house is an adder. For my house, I want them.
A $2.50 outlet over a $.39 outlet, usually the labor cost is far more than the material cost, and generally, better quality material can be easier and less labor to install. Generally, maybe not with outlets.
Over the short term there is an upfront cost difference. Over the long term, the cost difference lasts and is averaged over the 20 year design lifetime and the 50 year installed lifetime. Some guys are looking at the long term value, where the extra per day or per year cost of the adder is actually zero or negative (they saved money over the long term). They are looking at those spec grade outlets after 25 years and saying 'they look great and worked great over this lifetime, I am a genius' or they are looking at cheap outlets 25 years later and saying ' I saved 2.00 each on those, I beat the system, I have it over everybody'.
Really, with enough experence, both views are valid and statistically signficant. Do you know how many times a plumber saves $50. by buying and installing a toilet that needs to be plunged and flushed three times to operate. It's a big number.
Usually, the customer is clueless and only looking at the short term upfront cost. There are both a lot better quality products on the market compared to 10 or 20 years ago and there is still a lot of crap that gets built. Targeting the market price is usually resolved by choosing (forced to choose) lower quality material and lower quality labor. Some customers are afraid of this, or they may see the long term value, want nice things for themselves and others, and can be reasonable about spending more for upgrades.