New dinky do's

This is a portrait of myself striding purposely in to buy a pair of new shoes. Five minutes later I schlepped out ninety pounds lighter and not entirely convinced that the aforementioned footware actually fit me.

Question?
Why cant you get shoes in half sizes?

When I got home I went on to the interweb and found the same shoes at half the price - so I bought another two pairs.

Now I've got three pairs none of which fit? How did that happen?