There are many situation where JIRA administrators don't have suitable access to a server that host the application to review log files.
A good example of that sort of implementations is JIRA Hosted where "the admins" have access to the application only through web browser.

There are many advantages of such as feature. Perhaps the most significant are:

1. Monitor in a better way "helth" of the application - some of the user don't even know what is a web app server (Tomcat/Reisen) and where to look for the log files.
2. Diagnose problems in their early stage - e.g. mailhandler issues/misconfiguration are not visible without access to the log file.
3. Users would attempt to address common and obvious issues listed in the log file if the would have a "convenient" access to the logs.
4. In overall it should impact number of support request logged in SAC

Many web based application already include similar features.
A simple solution only displays the logs and allows to navigate between pages, where complex implementations include ability to create filters and are able to suggest possible resolutions for the know problems.