Thats the simplistic notion, yes.
However you're missing several points, the biggest is that it always bites people in the end. (I wont even address how this is having American companies that get tax breaks in this country and then shipping their workforce overseas without actually investing in the communities theyre located in).
So Person B makes 30k. Well How much is it going to take to teach person B how your company works? How much is going to cost extra to integrate them into your systems? How much more is it going to cost to fix their mistakes?
And god forbid, how much is it going to cost your company if he codes himself a hidden backdoor?
This has been going on since the mid-to-late 90s, with very little-to-no actual success.
So while wall street and accountants see it as a cost-savings in the short term, it ends up being quite a disaster by the end of it.