Your job as a landlord is to A) maximize monthly cash flow and B) maximize the value of your building. If you do not have meters you have failed at both, and therefore, I put you in the slumlord category, because in most cases it is extremely easy and cheap to install meters.
If for some reason you think you need to keep the utilities in your name that isn't relevant, you can still have meters and use them to determine how much to charge people. In a lot of states it's not legal to charge for any utilities without a meter. In most places however you can charge a reasonable fee for reading the submeter, or, you can even hire somebody to do it if you have a bunch of them. You can also have direct billing with the utility where they take care of all the work.
Even if you think you need to include "free" utilities in your rent for some reason, you need to have a meter to prevent waste. You only include a certain amount of the utility with the rent, not an unmetered, never ending supply. It is a proven fact a tenant will waste unmetered utilities, and this only increases your monthly expenses.
There is no smart argument for not having an individual meter for each tenant. The cost is too small in relation to the savings to be had and the increase in building value. A landlord that doesn't think they need meters is not somebody I can consider a professional. A smart tenant will avoid these properties knowing they will likely be overcharged for utilities. It's a bad way to run your business, no doubt about it.
And, since you asked about me personally, I make several hundred dollars every month in profit (legally) by submetering industrial utilities and charging my own rates that are higher than what the utility charges. More than some people rent entire units for.