genuinefake, I think I agree with you. But supposing you sent an email to him asking a question but didn't get a reply, or tried telephoning and got no answer. What would your reaction be? His business is a one man band so if he is away there is no one to stand in for him.
I have offered to check his emails but I can't answer his phone for him.
Personally I would leave a message that the site isn't going to be manned for the two week period he's away with a short explanation of why, I'd rather read a message that explains why it's 'unmanned' (everyone deserves a holiday) than exhausting any kind of effort to make contact by email and phone only to get the hump big time at the fact no one is answering (possible thought's that might go through my head are, still in business? just can't be bothered.)
If that is a home address on the website, or indeed if a home address can easily be found I would advise putting anything on the website that would make it obvious that the owner is not going to be living in their property.