Most companies guard their company name and logos with trade marks. You can guard your .NET domain by registering it. Many companies have already done that. Many other companies are in disputes over their .NET domains. Other companies have found that having a .NET allows them more flexibility.
Some companies address all internal corporate traffic through the .NET domain name.
Like internal email and a private internal web site. With the constant expansion of the Internet the capabilities and uses are ever expanding. Don't get caught in the future wishing you had taken a simple step that would reserve you expendability and assure your image stays in your control. This fee is for the first two years of the domain and is non-refundable. The process for doing this guarantees that the domain name will be moved to the new owner without making it available to the general public first.