"Farther out zoom levels" - where exactly? On the slippy map on the openstreetmap.org website?
This is only one data consumer out of many; and any of them is free to abbreviate names so they look better visually. For a data consumer, it is relatively easy to abbreviate spelled out terms, whereas guessing the correct spelled out word from the abbreviation is quite error prone.

The one exception is abbreviations that are themselves idiosyncratic (think CTA, FBI, ...) - these are generally accepted.

If you insist on having the abbreviated version tagged also, I guess the official_name tag could be worth looking into. However, not sure if you're aware or not, but Pace in particular isn't entirely consistent with how they name their stops themselves (e.g. in some cases, the names on the time table don't match the names on the list of posted stops, or the name on the ventra app, for that matter). 

In a way, abbreviating names so they display nicely on one particular map (e.g. the slippy map on osm.org) is a form of tagging for the renderer, which should generally be avoided - see here for more details: https://wiki.openstreetmap.org/wiki/Tagging_for_the_renderer

Here's some further info on names and abbreviations. Note that this isn't just talking about street names, but names in general. 
https://wiki.openstreetmap.org/wiki/Abbreviations

https://wiki.openstreetmap.org/wiki/Names#Abbreviation_(don't_do_it)
