It very much depends on the brand. I was initially buying the Monster drinks at a local gas station where I believe they were $3.25.

Eventually I transitioned to the Aldi brand which was I think around $1.

I meant specifically the Monster drinks. Red Bull for example is closer to 2 € here. The cheapest Aldi energy drinks are 0.29 €.

You pay a significant markup getting it at gas stations, but looking at a Monster on Walmart.com, it's still like $2.68. https://www.walmart.com/ip/Monster-Energy-Zero-Ultra-Energy-...

I guess it's cheaper in Europe.