Western, I don't think your wrong. Technically he could, yes. Would he excel? maybe, but probably not. It's my belief that him as an owner has certain obligations: quality checks, networking, checking in on employees, estimates, etc. Can he hire someone to do all of this? Sure, but will it result in significantly higher overhead? Yup. Most people make the mistake thinking that if you are charging a customer $200 per day for a weekly cleaning you are making that much. It's more of a profit of $50.00 for the owner after supplies, expenses, payroll, etc etc.
Will you hire people that already know the cleaning industry? Will you hire managers that know what to look for in a commercial or residential space? What if something goes wrong at an account, which it will, how will you meet the needs of that customer if you can't look them in the face?
Lastly, I believe companies succeed because of the vision, insight, knowledge, and goals the owner believes in and passes down to their employees which must be repeated over and over until it hurts you in the head so the people that you are managing have something to work for and goals they must achieve. Otherwise your employees will get bored, lose interest and quality in their job. It will be another case of high turnover in the cleaning industry thus leading to less quality work and you'll have to spend more time and money hiring new people and training them. If you aren't doing something (cleaning) that your employees are doing on a daily basis you will lose touch with them and they wont respect you for it.
Can he prove my philosophy wrong? Yes, so don't let me be the negative Nancy and kill your dreams. This is just my thoughts on the matter.