Just to give a little insight (hopefully) on why employers force people to use IE.
I work for a huge healthcare system in the IT dept and can tell you they still use IE and that is their "standard". Some of the reasons are that there are something like 40,000 computers in our environment and thru the years there have been thousands of applications written that were specifically written to work with IE.
It's just not that easy to change browsers when you have to test said applications to make sure every single one of them work with that new browser. This applies to both In house applications as well as vendor applications. Sometimes it's like pulling teeth to get a vendor to make even the smallest changes like an active x control or even a java setting.
In our case, it would be a very costly undertaking in terms of both money and man power. Money they feel is better spent on other things.