These lines are used IRL (FAA rules) when the visibility is less than 2 miles, or the cloud ceiling is less than 800 feet. However, the ATC controller may request certain aircraft hold short of them even if the weather is not below the standards stated above.
In Infinite Flight, most large airports have ILS crit. area hold lines. The airport editors have to add them in. The ATC controller constructing the ATIS information would be responsible of checking the weather conditions, but also making sure airports are equipped with ILS lines before adding the remark.
Controllers could potentially ghost users who pass by ILS lines, as they are technically entering the runway (the ILS lines function as normal hold short lines).
Thanks for giving my idea a read.