At the time, as a six year old with not yet developed deductive reasoning skills, I just thought the flags meant "I'm retarded."
Good thing I'm not growing up in Catalonia:
Women touting for customers on a rural highway outside Els Alamus near Lleida in Catalonia have been told to don the yellow fluorescent bibs or pay fines of 40 euros (£36) under road traffic laws.
Police claim the sex workers on the LL-11 road are not being specifically targeted because of what they do but because they posed a danger to drivers.
HT: Jesse Walker at reason.