They are different systems.
Ok, I can understand that.
Besides, it leaves room for "hope" that perhaps, sometimes in the future, they will be included in the global search.
Sure, one "can" go phisically to New Magincia and check them out BUT, it is handier an a considerable more time saver, to have the search engine check them all out at once and even sort prices of commodity wanted by lowest.......
Also, it would especially be handier in case of "buy" requests.....
Say that I have an extra surplus of iron ingots, I check from home whether there is up any "buy" request for iron ingots and if there is, and I like the price indicated, I turn my iron ingots into a deed, go to the New Magincia commodity buying vendor and sell them.... Would take like 5-10 minutes to do it all.....
As it is now, instead, I have to first go to New Magincia, check out all vendors to see who is buying and what, then go back to my place and get the commodity and then go back to New Magincia to sell it. It would take way more then if the commodity vendors were included in the global search......
So, there is a reason to include them also, IMHO.