If it’s so “expensive and valuable” then why have we been using it for decades to fill balloons here in the US?

good question! lots of people actually lobby to wither ban this (unlikely that it will happen) or at least make it more expensive.

Helium is increadibly important in the medical and science field. Having it “wasted” in party balloons is honestly, well, wasteful (if fun).

Helium is already getting more expensive, and it will only rise in the future

The reason it was so cheap in the last couple decades is, that the US basically sold off most, if not almost all of its stockpile, dumping the price on the market.

And now with very few sources for helium worldwide, the price will go up massively in the next couple years