Wow, your choices are interesting.
* Exxon: Massive amounts of technology have been ingested by the oil majors in the last 50 years. It is basically a high tech business at this point. Also, if we only focus on the physical work, fracking didn't exist 50 years ago, and now it is a major part of the industry. Again: Huge changes.
* Coke/Hershey: Think about how much automation exists in their manuf. Do any humans touch a "bottle" of Coca Cola before it is packaged? I doubt it in highly developed countries.
* Wells Fargo: the same as Exxon. Commercial banking has a fraction the number of employees _in proportion to their assets under management (AUM)_ compared to 50 years ago. How/Why? Automation / computers!