Using "Land Sales" as extra advertising - is this allowed?

Searching plots of land for sale sorted by price shows a few places at outrageous prices like L$999999999999 when it's clear that they aren't really for sale, just as extra advertising exposure.

Although I can't find anything specific in the CS, this does seem to amount to fraud, misrepresentation and deceit - and is just plain annoying.

Is there any way that some of these places that are clearly abusing the land sale system for cheap advertising can be dealt with?

Lewis