Genuine Q, honest: Does it matter ?
Not hugely. The reason I got some is that for me, my foot can rock side to side and this puts a lot of strain on the cleat attachment. Most of the time this starts to break down which may or may not write off the shoe. The ones with platform are certainly more stable for me, and allow the use of slightly more flexible shoes which are nicer to wear.
I think some of them have big platforms which can be used un-clipped, but mine aren’t that big. But they do add extra lateral support and it’s quite nice – when the cleat is the right height, of course.