The tension that you experienced is common in imperial and traditional systems of units. Here's another example for you: Carpenters working with wood use mixed feet, inches, and fractional inches (like 2' 5 3/8"), but machinists working with metal use exclusively decimal inches (like 29.375"). Both hold steadfast to their traditions and won't consider adopting the other system.
If you take a look at American grocery stores, you'll see things like: “40 × 16.9 FL OZ (1.05 PT) 500 mL BOTTLES / NET 676 FL OZ (5.28 GAL) 20 L” https://www.instacart.com/assets/domains/product-image/file/...
To dissect that product: It's a pack of 40× 500 mL of bottled water. I have zero problems with the metric labeling. But for the US customary units, you can see a jumble: decimal fluid ounces, decimal pints, a large number of fluid ounces, and decimal gallons. Note that the gallons can be broken down into mixed units (and some packaging does that); 676 fl oz = 5 gal 1 qt (0 pt) (0 cup) 4 fl oz exactly. The US units are basically "whatever I feel like using" (don't forget tsp and tbsp, which aren't used in the current example). The metric units for liquid consumer products are always mL and L, which greatly simplifies learning and comparison for the consumer.
