I remember reading somewhere that people are born with the ability to spell well or not, and that it has absolutely no bearing on their general intelligence level.
While I sometimes find spelling mistakes amusing, and feel they definitely shouldn't crop up often in schools for example, I can't help wondering where all you pedants think the non-spelling people should work?
Can't you put up with it if there is a spelling mistake on a fruit and veg stand or a shelf in a shop? Is it going to prevent you from buying exactly what you want to buy?
We need people working in jobs they are capable of doing, so that all differently abled people can contribute to society, surely?