We don’t have to; it doesn’t say we have to, but it says to use the abbreviations we have—meaning, if we’re going to abbreviate.
Taken from the text above: Furthermore, only the abbreviations supported by Waze should be used.
Perhaps a revision of the text would be appropriate to clear up these doubts about whether we have to or don’t have to.
This is perhaps the best point when it comes to choosing to abbreviate—the common sense mentioned by @sulstore—and I’m not just talking about these specific types of places; there are many others where it would apply.
And remembering that nowhere is it written that we must abbreviate; however, if you are going to abbreviate, the suggestion is to follow the abbreviations found in the Wazeopedia.
Regards