Actually the license file does not contain any sensitive information for you or for us. This is self-generated random key which just represents your order. You are right that it can be read easily, but this code is not valuable to anyone.
If that is of great concern to you, there is an option to hide the license file in your project's App_Data folder which has restricted access by default.
Here is what you can do to protect your license file:
1. Place the LicenseFile.xml in the project App_Data folder.
2. Add this line to the application web.config, section <cms>:
| <clear />
Hope this helps.
the Telerik team