I believe its a lot to do with the wording of the ads, as I still come across some (although they usually disappear within a day or two) that are trying to circumvent the TOS agreement changes.
Same goes with many other "for sale" sites.
It appears any that contain the words
tobacco, nicotine, or smoking seem to get canned.
If you inquire to the site admins they state usually without detail that its been removed due to its TOS.
So if you look at the TOS I can only assume they've related them as such:
tobacco = no tobacco sales are allowed
nicotine = no drug sales are allowed
smoking = see above.
Thats my take anyways.....
VapeOn,
Greg