We say in Eishes Chayil (at the end of Mishlei):
סדין עשתה ותמכר וחגור נתנה לכנעני
(The last word, “kena’ani” means merchant.)
Why does the Balabusta (or: Eishes Chayil) sell robes from home to customers herself wholesale, while giving the belts to a salesman for retail?
The marginal cost for distribution is higher for bulkier items, such as robes than for belts.
And there is a side point here about womanly modesty: she doesn’t travel around herself.
There’s another angle on this over here.