Online Resume

A colleague at work, who is directly involved in the hiring process, recently discovered that they could search resumes on a popular online job search website. I know that they have purposely searched to see if any current employees have their resumes on the site and when the last time was that it was made current. I keep my resume current on this site. I'm not actively looking for a new job but I do believe in keeping it current should an opportunity find me that betters myself and my family. Additionally, while I am a part of the company leadership team, I often find that I'm the last to be involved in discussions when decisions are basically already decided and feel like an afterthought to the team which also plays into why I keep my resume current online. How do I diplomatically explain this when the inevitable sit down occurs? I know that this colleague, who is at the same level as me within the company, will tell our direct supervisor when they find my resume and I know that it will at some point be something that I will be called in to discuss. TL;DR: I expect my coworker to tell my boss when she finds my resume online. How do I answer my boss when they question why I keep this current.