Why some hotels do not have rooms with 666 and floor with number 13?

In some countries, the number 666 and 13 are regarded as the bad luck numbers. So they are not available. But we don't have such kind of culture here. I love China

I think it has to do with the matter of association. Those numbers 666 and 13 are mostly associated with negative things or simply a bad omen. Like say, Friday the 13th. When the 13th of the month happens to fall on a Friday, most of us think and associate it that something bad might occur. As for 666, what I know about that number is that it associated with the devil and series of misfortunes.

Many countries have superstitious beliefs and act accordingly. They believe it will cause bad luck, and allow demons to enter the hotels. It's completely reasonable since 666 is the devil's number, and whoever takes the mark of the beast will suffer perpetually. I know that 13 is considered bad because of friday the 13th, when bad luck will occur, but I don't think they should taken that number away from hotel floors.

That's what I have heard. But I never verified it. I've stayed in several hotels and I never even asked for a specific room number or floor number. Nor did I check to see if there was no 13th floor or Room 666. But it's probably true.