Perhaps, but it spares me the need to double click or click-and-drag, both are which are the devil.
It is still 2 clicks per item. Either double click while at the vendor or right click once on each item and click again on "wares" to set the wares tag. Taking the time to keep your inventory tagged with wares items and then selling them when you get to the vendor with sell all wares actually ends up being 1 extra click over just double clicking everything into the vendor sell window.
