In the US (and probably anywhere with a goverment regulated food bureau like the FDA) its probably against the law to label rolled wheat as rolled oats. And any certified gluten free oats will not have wheat. Uncertified oats might have cross contamination though. Also wheat is normally brown/tan while oats are a creamy white to gray color.
I have switched to steel cut, a lot more filling and healthier, rolled and quick oats are normally steam treated and that breaks the fiber down a bit. The steel or stone cut take longer to cook but you can make them the day before so they are ready when you want them (and enjoy resistant starch).
I wonder if some people are confusing farina (more commonly known as Cream of Wheat in the USA) with oatmeal? Farina is most definitely wheat based, but can sometimes be mixed up with instant oatmeal.