I assume you're saying that in this hypothetical the hotel has so many rooms that it could host all of those people. In that case, no I probably wouldn't. Not because I think it's immoral, but because I don't know what repercussions I could face if I'm caught in my lie. If I knew for sure that there could be no repercussions then, yes, I probably would lie. I see literally no reason not to do so.