Others charge for it. Regardless, this is a feature that you may very well find yourself wanting in the future and you don't want to limit your ability to use these devices. Another feature that you need to investigate is technical support and training. Some of the cost savings of less expensive programs is offset by the lack of free technical support. The more complex the program, the more likely it is that you will need technical support.
Some companies even provide training classes around the country.
The internet is a terrific source of information about legal and every other kind of software. The ABA also maintains a web site with advise and information on legal technology. Many companies will allow you to download a demo to see if it meets your needs. Frequently, you can even download a full version time limited copy of the software. This is a big investment, both in time and money, and the consequences will affect you for a long time.