Inviting likers of posts on our Facebook pages has long been a way for us to grow our pages, and it has also been very successful, generally. But regardless of success, inviting people to like your page can hardly be considered spammy. We can assume that if someone likes a post, they will also like other of our content. It's an opening to send a valuable and relevant invitation.
Recently however, we have been getting this message when trying to Invite people:
We're sorry, more invitations to like this Page can't be sent today. Please try again later. If you think you're seeing this by mistake, please let us know.
The problem usually goes away after awhile, but the limit of how many invites we can send seems to have become drastically lower than usual. In the beginning we were able to send hundreds of these invites without any problems.
Why limit the number of invites?
The only reason why Facebook would limit this seems to be technical. Maybe they are worried of overloading the servers with spikes of people suddenly responding to invites, or just that a page will at some point have a huge amount of pending invites. The first seems more likely though.
The official explanation is that they want to avoid page owners "abusing" the feature. However, this is highly questionable, because when do you define our invites as "abusive". The answer to this question is pretty simple. You can't.
That is unless the invite feature on posts is connected with the normal page-invite feature.
It has long been possible for people to invite friends to like a page, and it is easy to see how this could be abused. A page owner could create a number of fake profiles, build a massive friends list on the fake profiles, and invite thousands. This is generally tedious, and not worth the time invested.
When trying to invite people by clicking on the "Invite friends to like this page" link, the same message pops up, suggesting that the two ways of inviting people are in fact connected. Which could explain the limits to invites some page owners are encountering.
Whatever the reason, the official explanation just seems unlikely. The invitation feature is, other than these limits, a nice way to grow a page. The result may also be different than the page promotion campaigns otherwise recommended by Facebook for gaining page likes.
A post could go viral, and thereby gain a lot of likes. And boosting a post can also be very successful. So there are good reasons to use the invitation feature, and one of the reasons is simply that it's there to be used.