A lizard with an attitude
Fears are something we can’t always explain. Some people are afraid of lizards, although this particular one seems completely innocent. Well, maybe not completely innocent. He might have an attitude, but that’s something you can work on, and other than that he seems harmless.
You can train dogs to lose their attitude, but is there such a think as gecko training? Anyway, this sign probably doesn’t mean in gecko-language what it means for us, so perhaps this person is just misinterpreting the situation, reading too much into it. You can’t judge a gecko by one flip of a finger.