I am sure I-73 will be built anyways. Martinsville is famous for its speedway and it needs to be connected to a interstate system. Roanoke has I-81, however Roanoke needs to be connected by another interstate, not only I-81. (all of them for economic reasons. one way or other, people who are against it.. are going to realize that its a necessary factor.
Replaced "needs"/"necessary" with "desired" and you're correct. It's not needed. It's desired.
The argument Strider is making for Interstate 73 would be a lot stronger if it was made from a Supply Chain/Logistics slant. Martinsville Speedway has two major events and does nothing to make a case for the interstate.
The manufacturing operations in Martinsville and Rocky Mount (look at how Henry County moved the alignment closer to an existing or is it planned Business Park) would certainly benefit from an Interstate standard highway.
Another example, MW Manufacturing (Windows) is located in Rocky Mount and would see a reduction in travel times as a result of a better standard highway. The direct access vs a connection via US 220 to the Interstate System is what Martinsville and Rocky Mount is looking for and that's why they are pushing it.
Roanoke would benefit more for possible distribution sites as it would be at the intersection of two interstates. It would allow companies to have quicker access South to Greensboro and into North Carolina - Quicker access into Southern West Virginia and Charleston in addition to the points NE & SW on 81.
But saying that because Martinsville has a race track that it's famous and they need the highway for it - holds no weight and is laughable.