Lot of useful mass there. Recycling makes a lot of sense, and we will wind up sorry if it's not done. Wouldn't take much to put it up into a very high parking orbit.
The only parking orbit is graveyard, above GEO - everything decays over a fairly short time period.
Of course bringing 7 tonnes to orbit is another story but even that is not so bad.
Interesting stat. Isn't a lot, but it sorta is, too.
I also would not bother reusing any of it.