Since it was prominent in one of his books, I believe Buffet holds to an old adage of not doing anything that you wouldn’t want published in the morning paper.
I wonder if Buffet still hangs out with Bill Gates.
Good question. As of 2018, according to this article, they are still BFF's:
Title: Inside the 27-year friendship of Bill Gates and Warren Buffett, who didn't even want to meet and now have each other on speed dial
https://www.businessinsider.com/bill-gates-warren-buffett-friendship-2018-3
Excerpt: Bill Gates and Warren Buffett are the second and fourth-wealthiest people on the planet. They also happen to be best friends.
But when they met 27 years ago, it was grudgingly. Each one was surprised at how much they enjoyed talking to the other.
Since then, they've been a tag team on political and philanthropic causes as well as mutual mentors. Plus, they love goofing off together.