I see no reason to allow this on my PC.
I came across a .BAT file to activate MalwareBytes Anti-Malware today. As I can assume from its code, it is altering something in the system drivers, which could be malicious I guess. Here's the code:
attrib -r %WINDIR%\system32\drivers\etc\hosts
SET NEWLINE=^& echo.
FIND /C /I "skipittok.com" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO ^127.0.0.1 skipittok.com>>%WINDIR%\system32\drivers\etc\hosts
FIND /C /I "keystone.mwbsys.com" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO ^127.0.0.1 keystone.mwbsys.com>>%WINDIR%\system32\drivers\etc\hosts
attrib +r %WINDIR%\system32\drivers\etc\hosts

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