I'm a surgeon. Needless to say, being a professional of any sort cuts into your hiking time. Add a family to that, and I have to tell you...
I regret nothing that I have done in this life, but rather those things that I didn't do. I could have done these epic hikes when I was younger and uncommitted, but I didn't. Now I may never do so- and that is a tragedy.
You're a fool if you don't do this.
(Oh, and doing these epic hikes AFTER law school isn't such a hot idea- all your prospective employers will be wondering why you have that big blank spot on your resume. Then you have to explain it, and they might not believe you and think you're covering something up, or if they do believe you they may be callous people who think that hiking is immature and pointless escapism and dislike you for not sharing their petty priorities, etc.)