Interesting question. Before I could take action, I'd need to know two things (at least):
1. What is the impact on the project?
2. What are the duties of the team lead? What is the team lead
accountable for?
90% of the PM's job is assessing the impact of an issue/risk/change/ on the project and communicating that impact to the relevant stakeholders. For example, the team lead setting his own working hours could have a negative effect on the project (limits collaboration), or it could have a positive effect on the project (greater productivity) (There is ample evidence that management endorsement of non-conformism significantly increases productivity). What is the real effect? Only after I know the impact on the project can I identify strategies to respond.
If the team lead is accountable for setting an example and a standard, then I've got no problem with his behavior. If the team lead is explicitly accountable for reducing bug count, implementing procedures to improve quality and training other programmers, then my response is to hold the team lead accountable for those behaviors. If the team lead is responsible for resolving bugs, then perhaps his practice of holding himself accountable for 85% of the bugs is effective? Is the team lead accountable for being social? (If so, why? How does social behavior lead to project closure?)
I suspect that the answer may be to discuss the quality improvement portion of the role with the team lead. Based on that discussion, either coach the team lead to a higher level of performance on that portion of his tasks, or reassign those tasks to someone better suited.
I'm very very skeptical of charges like "antisocial" and "nonconformist". The goal is to close the project successfully; if you can lead my project to closure, I don't care if you wear a plaid tutu and a tiara, discuss only Star Trek Voyager, and work only during prime numbered hours on alternate tuesdays. If you can't help me close my project, I don't care about your working hours or any other habit you have.