There are 2 ways I have seen NG delivered and distributed throughout a home. First the most common. fairly high pressure to the house and than into a regulator and a meter. It is regulated at this point to 7" WC and distributed. But in Minnesota at a friend's home I saw a weird thing. The gas went through a meter, but NOT a regulator. It was distributed at high pressure in flexible copper lines to each outlet and a regulator was at each outlet. IMO this is dangerous and an oddball way of doing it. Though at this point her house has not burned down...................yet
If you have the most common type there really is no need for a regulator on the grill. All that has to be done is "jet" the grill for 7" WC. I made this mistake when I gave my grill to son in law. I forgot I have a regulator on the gas line PRIOR to the gas quick connects. Well I gave him the grill jetted for (IIRC) 4" WC and it was running REALLY hot and he could not figure it out. Once I remembered I simply bored a new set of orifices for 7" and all is fine in there now.
So there is not a NEED for a regulator.
Many home appliances i,e, gas stove come with a regulator that is "switchable" between NG or LP as NG is 7" and LP is 11" WC and they come with an LP set of orifices too. Your grill doesn't need that. So again no need for a regulator. I kind of like one as it "evens" out the gas flow. IOW if your gas line is "at the end of the run" if a heavy use appliance turns on (like my 200k demand water heater) and the grill is running very low temp you COULD see a flame out. The regulator will even out those surges.