If you find in Google search a thumbtack link that does not go to the content in the link, then report it. Thumtack will often use local business names in their description, then when the consumer clicks on the links, they are led to a bid page, not to the business they advertised. This is called rich snippet spam. If you find it, report it.
https://support.google.com/webmasters/contact/rich_snippets_spam