Perhaps they are trying to explain the correlation between excitement and the smell of shoes...after all, I know many a person who gets mighty ecstatic when it comes to buying new shoes. Now whether or not they are still excited when they are placed on, in or near their mouth, remains to be seen. Im sure further study would need to be considered. However, the choice in images there certainly leaves one to speculate.
Re: Just a passing observation...
We still up for tether-ball later?