Mainframes are built to move huge amounts of data around. IBM did a fantastic job of building giant batch processing engines. Granted there are online options, but, to be honest, their bread and butter is huge amounts of data in and out. Because of that mentality, the fact that the course designers at Universities and older people in the IT field "growing up" with this technology and even the integration of the term "batch processing" into the general lexicon of life, people design systems to include batch processing.
OK, that may be too strong. Let’s say that the majority of the "reasons" for batch processing are actually replaceable with the phrase "because we’ve always done it that way". Batch processing, the processing of huge volumes of data in a scheduled, off prime time manner, is a relic of the mainframe and needs to be replaced with the idea of a batch of one. This idea of a batch of one is not new, as I`ve even used it on the mainframe. The user needed certain processing done immediately as opposed to that night and we dynamically created a job, complete with the JCL and necessary parameters, in a low priority job queue and the job was processed when the machine had spare cycles. It was batch, but a batch of one.
The idea is applicable in today’s world. When I ask people why they are creating a batch job they say something like "the printer is loaded with a certain paper at night so that is the only time we can do this". *WRONG* The processing can be done at anytime, the printing can only occur at night. Instead of doing a lot of processing at night, do the processing in an asynchronous manner throughout the day and do the printing at night. Split things into two pieces: processing and printing. They are two separate functions and do not need to be combined.
Let me rephrase in a more "global consulting" manner: by separating processes into their unique steps, you create more opportunities to provide value to the business client. Through a selective process of decoupling the steps in a business process you provide opportunity to inject new business functionality into a more flexible framework with less rework to the existing systems. Isn’t that really what the business user wants? More flexibility? More value?