You know the drill: kid runs up $1,300 bill buying donut upgrades in The Simpsons app without a parent's permission. Apple's been in and out of court over this very issue, and ultimately agreed to refund unwitting customers fleeced by their children. After that, it applied warning labels to so-called free apps, further distancing itself from any potential recourse.
As part of recent changes, Apple has stripped pricing labels from all free apps in its app listings, even if they don't contain in-app purchases. If you navigate to a specific app's page, you'll then be presented with the new 'Get' button. Google took a similar approach earlier this year, after it decided to remove free labels from the Play Store and simply ask users if they'd like to "Install" an app.
Are these updates going to affect how you download apps? Probably not. Apple is simply becoming more transparent in an attempt to better educate users (parents) about what the millions of apps on its store really want from you. More developers are adopting "freemium" models, which allows them to monetize their work as new features are added. However, as South Park hilariously points out, many games are designed to only let you progress if you part with your money first.