Big driving forces in computing power are financial services (I don't need to explain how much money is involved in this sector) and gaming (by some measures, equal to the economic size of Hollywood).
Financial services pushes things with customers demanding ever lower latencies and higher throughput's, we've also learnt a lot in terms of resilience and network design from FS.
Gaming also brought us very low latency, think online gaming and "lag", the code that goes into making sure your bullets in COD make sense is a work of art. Gaming also brought us GPU advances, which have lent themselves to other fields such as engineering and bio-sciences where certain types of calculation benefit from the skills of GPU's.
Agreed, code needs to become more efficient, but let's not assume all code is on par with Acrobat Reader or any number of fat apps out there, there is plenty going on from the software side pushing the needle further.