When I Travel I usually travel in C-Class for the company and stay very short in wherever I am going. A home-base to New York and back the next day is not a rare occasion. Longer trips may look like home-base - New York - Atlanta - Chicago - Detroit - Montreal - home base (all within the working week; the week-end is mine and the family's and not the comany's). That is done with a standard roller bag and a laptop case.
Our company rules stricly forbid that we check laptops for security reasons (mainly confidentiality), an personally I have no intention of having to buy shaving cream and toothpaste every time I see another city (unfortunalety I have to now). Also, seeing a customer based on the most likely lost luggage is not an option (the company does not pay for lost luggage and this would mean the extra suit I'd have to buy is on me! The airline won't pay for anything if they find the bag, and would send it step by step of my trip until it would finally reach me at home after 2 weeks).
And, since I have to use regular medication, I will under no circumstance let that go in the hold!
Banning hand luggage in general would simply but any airline out of business!