This is quite true.
Since the way a command is represented in a device is device-specific, due to the varied implementations, I guess the creators wisely chose a Command object along the lines of the classical COMMAND
pattern.
As per the spec and javadoc, the intention of the constants is to 'suggest' to the device on which position to place the command (aka button). In many phones, the Exit button always is placed on the right-side and the menu button is always placed on the left side.
So, if you want your users to feel comfortable with your application,
you should use the appropriate constants to ensure that the commands of your application are placed in appropriate places where the users are used to seeing those commands. If you defy them and use them willy-nilly, while it might amuse you, it might not amuse your users
The priority value, on top of the constants, can be used to decide the relative position of the command (highest priority button more accessible than the lowest priority button) to help in usability.
I guess these are unique considerations for a screen-restricted device such as a cell phone where screen space is at a premium.
