I wouldn't call UHT milk common. According to Wikipedia[0], it's less than 10% in Denmark, Greece, Norway, Finland, Sweden, Singapore and the U.K.

It seems the only places where it's "common" are Italy, Turkey, Switzerland, Germany, Czech Republic, Brazil, Portugal, Spain, France, and Belgium.

[0]: https://en.wikipedia.org/wiki/Ultra-high-temperature_process...

I guess it depends on the definition of "quickly" and also where you live.

In some cities I've lived, the expiration date of milk was often two or three weeks out. In other cities, it was 10 days maximum.

I think it's because dairies (and cows) are not equally plentiful in every part of the country.

One thing I have noticed is that in the places where regular milk expires in 10 days, the organic milk (which one family member drinks) doesn't expire for a month or more.

Sell by dates are basically a fiction. https://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety...

only limitation is: infant formula and false advertising (defined in https://www.law.cornell.edu/cfr/text/9/317.8 )

Sell by dates for eggs and milk vary by state in many cases, for milk I believe Montana has the strictest one (10-12 days after pasteurization) but I've seen references to at least 20 states having their own regulations.

UHT pasteurization

Maybe neither you nor grandparent know about UHT treatment of milk, and how it's common outside America and uncommon inside.

Seems to be at every single grocery store I have ever shopped in for the past at least 5 years.

Not every milk is UHT but every grocery store offers it.

> Not every milk is UHT but every grocery store offers it.

But what about Costco (or other bulk-only sources), which is, really, the whole point of the thread (and original comment)?