Yesterday we were unexpectedly asked to stop taking photos outside The Venetian resort. This has never happened before - inside the shops is restricted in the same fashion and this is better known - but the security assured us that it is standard procedure and that, before taking any photos on the grounds, you must contact management in order to request permission. I believe permission to take photos is free, but you must inquire in advance (the security said even requesting it same-day would be possible).