You're given weeks to refresh your knowledge ahead of a Google interview. They tell you the basic CS fundamentals that are going to be covered. Binary trees are MOST ASSUREDLY on that list. They just don't have time during 45 minute interviews to let the candidate go on the Internet to look things up they should already have come prepared for.
Anecdotally, at a previous company, we tried an "open book" (i.e. you can use the web) interview policy for a few interviews. It was a train wreck.
Anecdotally, at a previous company, we tried an "open book" (i.e. you can use the web) interview policy for a few interviews. It was a train wreck.