They really haven't
Pjaca was €23m
Pjanic was €32m
Benatia was €3m loan with €17m option to buy him at the end of the loan
Dani Alves was a free transfer
And they sold Moratta to Madrid for €30m
So they have basically net spend €28m so far
In terms of wages Alves is prob on a big one and Benatia and Pjanic will also earn a decent wage but they have lost the wage of Cuadrado and Moratta so all in all not much difference there.
I don't think Juve would spend €94m without selling Pogba but it is not true they have spend an awfull lot. In fact they are a very economical club and their books are usually in order. At the end of the summer they will probably have earned more money than they have spend.
The thing actually is, I do think it is possible but very unlikley Juve might actually be able to afford Higuain without selling Pogba. They never spend much and every season they get money from CL money and winning the serie A, so it is not unlikley they might have build up some reserve cash. If they would sell some further players like Zaza (20m), Manzukic(20m), Pereya(18m) who all still look like leaving, they might actually be able to afford it without selling Pogba. But must say I think it is unlikley because it feels very unlike Juve.