If I have understood everything correctly. First of all no more xch can be created ever after the 45 day viacoin exchange period. Yet everytime you do something within clearinghouse like for example create an asset or contract to do so requires the destruction/burn of one or more xch. This would eventually mean that the world would run out of xch, so then what?
Fees in XCH are not carved in stone forever, they can (and will) be repeatedly adjusted for XCH to be slightly deflationary in the future, that is all. You can have for example 0.1% decrease in supply of XCH each year and this can go on forever, geometrical sequence never ends.
Such a shortage of XCH as you desribe would be a real paradise for XCH owners. But there is no need to worry about this.
I am somewhat worried by another thing. If very many VIAs are sold this way and there is no limit, a large portion of VIA supply will be in control of one man (Drak), this is dangerous. Large concentration of ownership will undermine confidence in VIA on the market. VIA will be ridiculed by rival coins with (pretended) fair distribution and so on.