Question regarding $XDG_DATA_DIRS

Hi.

I noticed that the default value has a trailing slash for both directories:

> If $XDG_DATA_DIRS is either not set or empty, a value equal to /usr/local/share/:/usr/share/ should be used.

I was wondering what's the benefit of including a trailing slash? Is
there a specific purpose to it or is it a typo? With all due respect,
it looks so out of place. Path-related variables usually strip it off.

Sorry if I'm asking in the wrong place.

Cheers,
Akbar.