Earlier quoted context omitted.
If you write MIT code you expect them not to strip your license out in derivative works. This is exactly what license are for and GitHub is blatantly violating it while people applaud.
Maybe read the MIT license before you grab the pitchforks: "The above copyright notice and this permission notice shall be included in all COPIES OR SUBSTANTIAL PORTIONS of the Software." Reusing a snippet doesn't require reproducing the MIT license. People who publish MIT software know they're basically giving their code out with basically no strings attached. However, GitHub should be careful with the GPL variety.
This does not relieve the person using the code of the responsibility to make that determination, so anyone who is re-using code shown to them by this automated tool is doing it without having fulfilled their responsibility under the license. The fact that they don't know they are doing this, because the tool is not telling them, doesn't change that.
> People who publish MIT software know they're basically giving their code out with basically no strings attached.
No, they aren't. The license has terms. Using an automated tool that doesn't tell you when you are re-using existing licensed code, or whether your re-use is within the terms of the license, doesn't mean you can just ignore the license. It means you're re-using code without knowing whether or not you're violating a license.