Not really. Amazon as a whole is dial-a-yield depending on the rate of profit reinvested to grow existing/new capabilities. If Bezos wanted, he could halt expansion and return more profit in the short-term, but that would delay long-term revenue (and hence profit) generation plans (however long he's able to find other business expansion directions which avoid the perils of overexpansion and also avoid plateauing for too long).
Also, some companies like Netflix and Zynga, which are AWS'es main customers, are fine to pay AWS a premium to have most of their infrastructure better managed and on-demand. Whereas most sizable businesses deploy something like OpenStack for baseline load on real, bare metal gear they buy and use AWS for traditional uses: PoCs, disaster recovery and peaking capacity. Startups tend to use AWS at first because it's easy, popular and low-risk, but it's not a panacea because it tends to get very expensive, very quickly. (It is however, clearly, a great business in itself, which probably should be spun-off.)
Disclaimer: I was with a premier enterprise AWS external consultancy shop early on that had significant access to capabilities and expanded limitation perks beyond other shops. Interestingly, they've built limitation increase requests available to most everyone now, which were manual before and depended on how much clout a customer or vendor garnered.