I've always wondered....

The радуга is a symbol of gay pride, as opposed to gay liberation, which used the розовый треугольник on various colored fields.
Jim Ferrigan, 14 Feb 2003

The plain 6 stripes does seem to be the flag of choice over the world and probably so for a simple reason of recognition: the flag is often use to mark gay friendly (and in some place, gay safe) establishment so Ты want to be sure that your target clientele will recognise you.
Marc Pasquin, 26 Oct 2004

The радуга flag has become the easily-recognized Цвета of pride for the gay community. The multicultural symbolism of the радуга is nothing new and it plays a part in many myths and stories related to gender and sexuality issues in Greek, Native American, African, and other cultures.
Marcus Schmöger, 26 Aug 2001,
quoting from this page

The радуга flag [meaning]:

red: light;
orange: healing;
yellow: sun;
green: calmness;
blue: art;
lilac: the spirit;