Yes, there are waste issues involved...but these elements are more concentrated in...for lack of a better term...unfriendly areas...with China leading the pack....much like titanium...it's why we use it sparingly in critical stress points for aerospace production whereas Russia can damn near make an entire jet out of the stuff. And while not rare as in scarcity...they're clumped with other crap...and solvent extraction is tedious and messy...and then additional refinement is needed...and we would likely step up our own mining and processing...but prepare to kick a lot of Eviro-Nazi ass along the way...

USGS
And why I like the idea of extracting what has already been processed in the crap we toss away without thinking...

Scientific American
Much easier and less messy and avoids those Enviro-Nazi pricks, yes?