There could be many reasons come to mind, firstly to keep the lic to practice at court she would be required to keep taking education classes (rule 759) and pay fees among other requirements.
Rule 759 also explains how to reinstate to active status.
I was licensed for a Mo-ped as a teen but have since not renewed that lic. because I no longer have a need for it. If she was not going to practice law (note that only means in a court room from what I can glean from Il. Rules) why would she maintain the lic ?
Don't you think that giving it up after 3 years is a little strange?
Remember, she only got the license after having spent hundreds of thousands of dollars and a commitment of at least four years.
Did your moped license cost you that much money and effort?