This subject has come up a number of times (usually on forums.) The short answer is that, in theory, keeping it a regional only class keeps it relatively affordable. In reality, this may not be true. If you wish to compete in Majors events, IT cars can be entered in either Super Touring (STL/STU) or Production.

There is a small contingent of IT competitors who would like the category to become Majors/Runoffs eligible classes. Whenever the noise level gets above some arbitrary point the BoD hears from others who oppose the idea.

As to whether or not regional only status keeps costs down, please name one class that went from regional to national status that didn't experience a significant increase in cost to be competitive.