They absolutely need to know the demand of each unit, if another home off the same feed is built later or upgrades their service they need to know if the existing capacity is sufficient or if components need to be upgraded.
No they don't.
This information is only relevant for the local provider that physically connects to your home, not for the company selling you the elecricity.
But I increasingly get the feeling that you don't have a free electricity consumer market in the US?
That would actually come as a surprise to me, but would explain some of the comprehension problems that l have seen and experienced myself in this thread.