Mmmmm cake. So if you were given a piece of cake what would you do with it? Look at it? Sit on it? Throw it? Well no matter what YOU would do with it most people would eat it. This is called having a piece of cake and putting it in your mouth and swallowing it.
So what’s with the expression “Have your cake and eat it too”? I mean if you’re going to get a piece of cake you’re going to want to eat it. Well according to Wikipedia that isn’t the original expression. The original is actually reversed so it goes more like “Eat your cake and have it too”. This implies that you can’t eat your cake and then have it.
Somewhere, sometime, something went stupid. Someone reversed the expression and we got this whole new illogical one. I mean, what fun would a completely logical and sensible expression be anyway? Someone said it wrong and then spreading like wildfire, it became adopted as canon and BAM!, we have a whole new expression, as stupid as it may be, with the original being forgotten.
So next time someone says that expression, please try and correct them. Let them know why it is wrong how they said it. Maybe together we can restore it to its proper usage and this will be a forgotten entry in time.