It would make it more difficult to map the architecture of the LAN from the inside. This helps security but hinders troubleshooting. It's up to the people running the show to determine the balance between those two needs.
If you must, you can trace the network hops in different ways. Hping3 has many methods for tracing hops in the network. Give it a whirl. However you may anger you networks gods if they have tight/paranoid security.
Tracert is typically blocked by Sysadmins / Network admins to prevent a mechanism with which one could potentially map the resources on your network.
You should also note that trace route can use different protocols, they may not all be blocked.
It would make it more difficult to map the architecture of the LAN from the inside. This helps security but hinders troubleshooting. It's up to the people running the show to determine the balance between those two needs.
If you must, you can trace the network hops in different ways. Hping3 has many methods for tracing hops in the network. Give it a whirl. However you may anger you networks gods if they have tight/paranoid security.
mtr http://en.wikipedia.org/wiki/MTR_(software)
is a little easier to use, and can give realtime feedback on networks stats.
It has a number of detection methods, however it's not as cool as hping.
hope this helps