Do M&A bankers use WeWork or Regus?

I was at a temp office (Regus) and saw a retired founder / large shareholder of a public company walking in and going into a conference room. He doesn't live in this city (as far as I can tell) and I can't think of any reason for him to go to a temp office. I mean, he's very wealthy and retired.

So my question s, do M&A bankers or lawyers schedule meetings at temp offices to keep the meeting private from their colleagues or for some other reason? It wasn't downtown either, it was near a residential neighborhood about a fifteen minute drive from downtown. The only reason I recognized him is that I'm a business nerd, otherwise I'm sure nobody else there recognized him.