Snapchat Lied!
You have probably heard that Snapchat lied to all of its users. The entire draw to the application was on the premise that the pictures/videos (now text) will be deleted forever once its been viewed; and if the recipient took a screenshot, Snapchat would inform the send. It was a simple concept.
So Snapchat continues to delete the images/videos that have been viewed. But the recent settlement with the FTC deals with that fact that pictures and videos can be saved through back channels (including files in a folder locally stored by Snapchat), which is no surprise. This goes against Snapchat's "disappears forever" claim and they no longer warn all users that a screenshot has been taken (e.g. iOS 7 users).
In addition to those claims, Snapchat was also requesting location data. But supposedly Snapchat isn't using the data to track you; the company said it is to provide "more interesting filters" (e.g. weather/speed).
Just like everything you post on the Internet, you have assume that it'll be on the Internet forever. Nothing will ever truly disappear forever, 100% of the time. It could be as simple as taking a picture with another device. As a Snapchat user, I find it convenient not having to deal with picture/videos (sent or received) that I don't want to have to organize/delete/store with those that actually want to keep. It's quick method of communication without much drawbacks.
So what if Snapchat breaks their policy or their security claims? It'll have to pay $16k a day. And for a company that is current not making any profit, that could be a lot of money. Lesson Learned: Don't claim for something you can't do. Be more transparent.
As users, we must be self-responsible and use appropriate caution. Just imagine, if we trusted all those "I'm an wealthy price. Send me your bank account information, and I send you tons of mail" emails.