Not at all.
Actual requirements and legalities will differ between countries.
#disclaimer: I am not a law professional
A couple of companies I have worked for in the telco industry have an underwritten contractual agreement with the government whereby all reasonable efforts must be made to retain records for a certain period of time (I am not going to elaborate on the lengths). If it is found that these steps have not been taken the companies can be penalised financially by the government for not keeping their contractual agreement. The information which is held will often be required to assist law enforcement with confirming the location of a person or where a transaction may have taken place from. Sorry if this is a bit vague but vagueness is on purpose.
That being said, relating it to something more familiar to the users here:
Transaction records such as purchases are often kept for a decent length of time should there discrepancies or fraudulent recovery action.
Having the Player/Guild ID historical information and transaction material is something which can be useful for covering your backside as well as supporting legal action should they be required.
Okay, got it. First post was a little vague to me, this one is fine. Seeing that you have some experience with this kind of thing, couldn't they just archive all the information of the guild ID, transactions, etc of the guild for supporting legal action if needed and still open up the guild name for future players to choose to use?