We use whole numbers for temperature because nobody can tell the difference in +/- 1°C (or +/- 1°F, for that matter). You might see a few weather apps reporting to the nearest .5 (which is about 1°F) or maybe even .1, but they are unnecesary. You only need precision if you're doing something with the value (mainly STEM-y stuff), and 99% of those calcs are done in Kelvin or Celsius.

Fahrenheit didn't do it for the precision, he did it so that it would be easier to draw the scale on analog gauhes. This is outdated, since we live in a digital world, and gauges are made by machines that don't care if they're dividing things into six, 10, or 37.23.

Cooking uses (kilo)grams and (milli)litres for the most part.

Americans get more shit because, unlike the British, most Americans simply don't understand the metric system, and are proud of it. A Brit or a Canadian would tell you their height in feet, but could at least ballpark it in metres. Metric is really not that hard. E.g. A litre of water has a mass of 1kg, and occupies 1000 cubic centimetres, or 1 cubic decimetre (0.001m³). If I walk a thousand metres, I've walked a kilometre, which is 1 million millimetres, or 100,000cm. Do you see the beauty of this? Compare that to 1760 yards in a mile, or 16 ounces in a pound. Metric is just a simpler, more sensical system! Having standard measurements is important, and sure at this point computers will do the conversion for us, but it's just silly that one country drag their feet like this.