@nfgo: Gentiles are not obligated according to Jewish Law to cover their heads ever or when attending a Jewish program.
Most gentiles do it out of respect for their “hosts”.
Some might cover their heads for all the reasons you mentioned. We are living in the 21st Century and people are more educated now than they were decades ago and understand the culture/traditions of their “neighbors”.
It is very disrespectful in the Japanese culture for an individual to cross their legs with the sole of their shoe showing.
Also, in the Japanese working world, peoples’ business cards are not placed in a presentation folder but handed to those attending the presentation. It seems to be ceremonial.