By widescreen they mean letterboxed w/s, I don't know of any retail VHS which are anamorphic w/s.
Anamorphic VHS is possible, e.g. if you record a 16:9 broadcast off digital cable/satellite TV, I think there's a widescreen signal in one of the video lines in the overscan area of the picture. One of my VCRs will even autoswitch a TV to 16:9 mode when playing back a recording of a 16:9 programme - a feature my DVD recorder is sadly lacking!