I doubt that Chai reads all the posts on every forum & even if he did would remember who had ordered what so I would think he has just sent you what he has got at the time.
That would annoy me, ok you didn't specify a part number but you did go by a picture in his webshop. I know that sellers have the right to substitute items if it's in their terms and conditions but if you had ordered these & had already done the work for this style to fit or were replacing existing units the new ones he has sent wouldn't fit.
I got caught out with some electronic components I bought from RS in a similar way, my fault I suppose for not reading the technical spec properly but not being a whizz with electronics I just went by the picture. RS were very quick to point that out to me so won't order from them again if I'm not 100% sure exactly what I need, what it looks like & how to use it properly lol.