While I have never heard of someone referring to 7 as a lucky number, 7 is the most common sum of two rolled dice. So I can see how people would regard it as a lucky number. Along the same lines, I assume that someone who mentions 42 as a random number has at least some interest in science fiction.
I prefer to calculate with numbers, and don't pay much attention to superstitions around them. I don't gamble, nor much pay attention to conversations about gambling, so I pretty much ignore any mention of lucky numbers when such topics arise (aside from knowing that some people have lucky numbers). If you refer being isolated from a particular aspect of life living under a rock, so be it. Though I will point out that I like wide open space. I'm more of an astronomer than a geologist!