Grid CallbackDataProvider and AbstractGridSingleSelectionModel

Whenever I create a Grid and use the CallbackDataProvider I’m able to provide a idGetter (ValueProvider<T, Object>). This ID provider is used for each column to find the same row again. But the AbstractGridSingleSelectionModel only uses the hashCode and equals method of the row object. Why is there no possibility to provide a idGetter for the selection model also?