Brilliant question ! I think such people do that to be part of the crowd when in public but privately, as you said, they leave. This reminds me of a Modi tour to Germany earlier this year where in a gathering of his admirers a brainwashed bhagwa boy sang :
Bharat, Bharat, Bharat... Now in the beginning of the song which isn't there in this vid is something like "Mera janm bhoomi Bharat, mera karm bhoomi Bharat...". "Janm bhoomi" means the land of birth. Karm bhoomi means a place where one works. So this boy's parents having brainwashed him with this nonsense about "Karm bhoomi Bharat" why don't they leave Germany to their "Karm bhoomi" and "Janm bhoomi" ?