I regularly see MacBooks being issued in corporate and higher education environments where employees are either tasked with buying or were given the extra cables. Again, those cables break too regularly for comfort (power/adapter ~1 break per year). There must be some great deals going on cause I can't see why they keep doing it. If it's cost, well, my 2012 Air works just as good as the day I bought it.
Your metaphor, more accurately: "My company said I would be given a truck for my work. Why are we all driving sedans with attached trailers?"