Originally Posted by graraps

Rubbish! I always suspected something was wrong. Indeed, KE do have a first class, and the F pax may be offended if you turn up dressed in a manner that would belong to a higher class of service.
Please ignore my previous recommendation. Appropriate attire for business in a 3-class service would be a combination of bikini, cossack hat, gloves, sandals and nylon socks.