"Government regulation is what creates most barriers to entry."
Maybe the government regulation as practised by cronyist goverments. Seriously, I don't think that a hypothetical government enforcing standards for square feet measurement would create a huge barrier to entry into the property business.
As soon as there's a law about how to calculate square footage there will either be an agency to do the calculate the square footage, an agency to enforce it, or both. Oh, and some sort of tax/fee levied against commercial land-lords and the possibility of lawsuits all around. And that's assuming that the law doesn't require auditing and/or some sort of compliance documentation. I don't think you're really allowing for how onerous even "simple" regulation can be when lawyers and bureaucrats get ahold of it.
Weights and measures are already regulated in the U.S. This is why, when you pay for a gallon of gas, you can be sure you are getting an actual, standard gallon of gasoline. This in itself doesn't seem to create a barrier to entry for gas stations and protects the consumer.
In the US at least the state DOT's do go out and check on the pumps and check both that they are calibrated for liquid measure and that the gasoline falls within the acceptable temperature range (because warmer gasoline occupies a greater volume).
As soon as there's a law about how to calculate square footage there will either be an agency to do the calculate the square footage, an agency to enforce it, or both. Oh, and some sort of tax/fee levied against commercial land-lords and the possibility of lawsuits all around
You'd prefer it to be legal if your gallon of gas only actually contained 3/4 of a gallon?
if you worry about what laws you might be breaking every time you want to do something, you'll never get anywhere. i suspect that most new restaurants are in violation of dozens if not hundreds of laws, but in reality they either aren't enforced or the owners are given an opportunity to fix whatever is wrong without penalty. follow the laws you know, don't go looking for ones you might be breaking, and when the government tells you that you're breaking a law remind them how many people you're employing.
You're probably right in some sense, but there are many laws --- liquor licensing, health inspection, and employment, in particular --- that are actively enforced and a day-to-day reality for restauranteurs.