Ear plugs are used for times when the horse needs hearing protection or for when the horse is in a situation where little noises will cause a distraction. On windy days, I will put ear plugs on my horse because he will just keep spooking at the noises the wind makes.
Fly sheets are usually a light color, or the new trend is a zebra pattern. Usually they don't make it uncomfortable for a horse. I have a riding fly sheet in blue and my horse is not any hotter when he wears it.
* I'm often reading and posting from mobile and Siri loves to make a mockery of the English language.