Its monopoly rent, remember that these industries were propped up by VCs and ran on losses for a long time. So now its time for VCs to make a ROI, thus prices are higher than they should be.

my best guess is monopoly rent... once you've moved all your stuff to the cloud you become dependent on them and they know that

once hundreds and thousands of companies do it the cloud providers gain a lot of leverage

i imagine there are some pretty hefty operating expenses they have to pay as well to operate at such an enormous scale, so their costs don't necessarily decrease when they add more customers