Every time an extra cost or increase is imposed, you quietly loss a couple of more cars off the grid.
Recently we have had an the following
H+S levy
Entry cost
Transponder hire to $70.00
Fireproof underwear
HANS, which will extend to a new helmet.
etc no doubt.

The promoters and owners are fine to impose these requirements, but equally folks can also choose not to enter, and this is what has been happening for some time.
No doubt, I will buy a hans in my own good time, however, at this stage, the 2 cars we were entering for HD will, due to cost , will not be running. I wonder how many others will also quietly drop away.

I recall the organizers running the wellington sevens, ( not realizing, at that point, who really held the power) decided to clamp down on the drunken revelers. So the drinkers stayed away and everybody was happy. Except bugger all people attended, and it was likely only then, that it dawned on them, that the folks they alienated, by imposing these requirements, were actually their customer base.