There are a number of Twitter accounts that have discovered that they can race through a list of tweets, perhaps from a Twitter search on "real estate" or some other key words, and can favorite the whole list without those showing up on their Twitter feed but nevertheless automatically notifying the original posters that their tweets have been favorited (which would otherwise be considered a favor/nice, thoughtful, sincere gesture).
We've been checking the profile of those favoriting a number of our tweets, and when checking their Favorites, have found many of them are favoriting so many tweets that some of them may even be using bots to do it.
We tweeted on this subject hoping to draw it to the attention of others who would never employ such methods and who wouldn't want to encourage the practice by following those who are doing it or by visiting their websites, etc.
We are actually blocking those who are doing this, as we don't want to be annoyed by such disingenuous favorites.
Users are favoriting [many] dozens of tweets/hour [even minute] (not following) for traffic/followers. We block them. Check favorites of those favoriting tweets.
— PropertyPak (@PropertyPak) March 27, 2013
Some of them are favoriting many dozens of tweets per minute.
Non-followers use a bot to favorite tweets. Settings > Email notifications > select "My Tweets are marked as favorite" "By people I follow."
— PropertyPak (@PropertyPak) April 9, 2013