On the contrary, as a stupid American, I'm grateful for the imperial system because it doesn't require much thinking at all.
The intuitiveness of the imperial units actually don't demand much thinking from my American pea brain: an inch is about the width of my thumb, a pound is about the weight of how much meat/grain I can fit in my hands, a mile is about a thousand paces - it's actually quite simple and intuitive, which is perfect for a dumb stupid American like me.
I can't imagine doing something like woodworking without my brainlet system. Inches are a nice "bite-size" unit that fractionates quite nicely for cutting wood. They don't make me think too much. In metric, my thumb would be about 2.53 centimeters, the kerf of my saw is 1/8 an inch, and that's like 253/800cm as a fraction - yikes! An inch is a good whole number to start working from.
And then like - what's a centimeter even? It's one hundredth of one ten-millionth of the distance between the North Pole and the Equator passing through Paris. Woah - get me outta here! That's just too much numerology for me. And my brain can't relate to or conceptualize that. Again, because I'm just so stupid, and American. I have to stick to the simple stuff: thumb -> inch, pound -> fits in my hands, mile -> thousand paces, gallon -> 10 pounds of water.
A gallon of water weighs 8.3 pounds, so your estimate of 10 pounds is about 20% too high. To add to what someone else posted in terms of metric to “intutive” equivalences, 1 km is about 600 paces (for me, it’s also the distance from my house to the Asian market)
People living in metric countries have these sorts of “intuitive” relationships figured out. If you ever go to Europe, you will not see people anxiously furrowing their brows over their calculators to figure out how much things weigh or how far it is to the end of the block.
It's easy enough to skip on the exercise if you wish. All my measuring tools support metric right next to imperial. All the food on the shelf at the market is measured both ways. I can live a metric life if I want to.
Speaking as someone who grew up with the metric system before moving to America: Because growing up, we never had to convert between different measuring systems.
Everything was easy to do in your head:
5cm + 15cm = 20cm
0.5kg + 0.15kg = 0.65kg
2900mm / 2 = 1450mm.
Now I'm forced to do mental gymnastics like:
5/8" + 7/16" = ???
2'9 1/4" + 14" = ???
11'4"1/4 / 2 = ???
1lb9oz / 2 = ???
It's not impossible, but it takes me a lot more time to think through these things, and often they are impossible to even punch into a calculator. Adding fractions of an inch in my head was not something I learned in school (honestly, my experience since moving to the US is that most adult Americans also struggle to add fractions of an inch).
There's give and take. A unit based on 1/12th makes one third, one half, and one quarter all even divisions.
It's just not that big a deal in my experience. And if I want to use millimeters, every ruler and tape measure has those too. For all the bitching about the US not using metric, we in fact use it for many things. But it's customary to use imperial for discussion, and I don't get why that hurts people's feelings. I don't care about the UK weighing people in stones...
Yeah, ability to employ both systems and translate between them is quite useful. It might be similar to native bilingualism.
Even outside of the legacy imperial unit systems, there will always be units not nicely expressed in metric units that are handy nevertheless and good to know and use. Like electron-volts.
Now that you're mentioning that, why doesn't the default calculator app on a phone have prominent functionality for that, it's so useful in everyday life.
Sure. But it's the constant bitching about it. We know, we know, you [metaphorically, not you personally necessarily] like metric better. The US uses metric for all kinds of things, in fact! And the UK still uses imperial for some things. Conversions are not hard, and hearing people bitch about it in every thread is tedious.
Aside from some internet memery, no one cares too much if you use metric or imperial, but mixing the two is a special kind of accursed.
Metric is more clean. Example: you have a cube of 1 meter, filled halfway with water. You can calculate the volume of water as being 1 * 1 * 0.5 cubic meter. 1 cubic meter is 1000 liter (ho ho, the magic already manifests), so 0.5 cubic meter is 500 liter. I even know the approximate weight is 500kg, as 1 liter of water ≈ 1 kilo.
Doing this in cubic yards/feet + fluidic ounce + pounds is not even in the same universe in terms of elegance or ease-of-use. Swapping the fluidic ounce to liter does not solve that and probably introduces whackier ratios.
That does not mean you are a bad person for using imperial, but stating that "its easy to convert" isn't wholly fair either.
Part of the marketing strategy in getting the U.S. and other minorities to adopt the metric system has been to attach a morality component to it, which results in any dissent being met with shaming and emotional appeals, as the morality component supersedes the logical component.
