Cleaning the Barrel of a New Gun Necessary?

So in the past whether it was Kral, Hatsan, Umarex, Gamo, etc I’d clean the barrel of a new gun and it would come out grimy and greasy etc.... I suppose the stuff they keep in the barrel when shipping was what I was pulling out. When I got my Crown Continuum I did the same thing and the patches were darn near clean from first run (I ordered that gun as soon as I could and waited 6 weeks for it)... I didn’t even bother after one pass and It’s been a tack driver since... do you suppose the fact FX units are spoken for by in large before being shipped and or being sold as soon as they hit the shelves has anything to do with it? I’ve never seen such a clean barrel on a air gun before when getting it. Have an impact in 30 coming this week that I have paid for and waited three months for. I suspect the barrel will be equally clean upon arrival... but maybe I’m wrong... ? The continuum wasn’T cleaned before shooting, didn’t need to be and was accurate as could be.... thoughts? 
 
Some dealers open the packages and test the guns before they ship them. It would be my guess that they would run a couple of patches through them before testing. Other guns are drop shipped directly form the manufacturer with all of the protective lube still in the barrel. I always run a patch though my new guns and as yet have never had one with an already clean barrel. So to run a patch through it just to check would likely be a good idea.
 
People saying their barrel is clean. I doubt it. Unless first owner just cleaned it and then ship it, there is no way for it to be clean. Some barrels will be dirtier than others, but all barrels will have some junk in them. I bought an fx impact from airgun depot. I ran a white patch though it and came out a little grey. I bought a slug liner from Utah airgun. Ran a white patch though it and came out grey too. It ain't like dirty black, but it sure ain't clean. Clean would be running a white patch though it and came out white. Those who claim theirs is clean, I doubt it is really clean. 
 
It's well known that barrels have to be re-seasoned after cleaning.

If you start out with an uncleaned barrel you will be in unknown territory when you finally clean it anyway.

Better to start out with a clean barrel right off the bat, and see how long it takes to be seasoned and what it can do at various stages. Then you will always know for the future when you are losing accuracy and need cleaning and where you will be starting from when you do.

I also now always add this step to cleaning a new rifle. I coat the sides and nose of a couple dozen pellets with JB Bore Cleaner paste and shoot them... This is a poor man's polish job. I've found from using it on older guns that it seems to help them foul slower afterwards too. Smoother bore, less for crud to adhere to is my belief. I don't do it every time, just the first time and then after 3 or 4 regular cleanings do it again. On my pellet rifles I don't clean till accuracy drops which can be thousands of shots. Big bore slug airguns I clean as necessary, every 150 to 200 shots then re-season with 10 shots. I might redo the JB treatment in 4 or 5 regular cleanings there too. But not 20 or 25 coated shots like the first time, just 2 seem to remove a lot that the brushes and Ballistol doesn't.