Until this thread, I have never encountered the term "bar tariff" for a list of drink prices, or "energy tariff" instead of rate. Those uses are simply not American English, and you would be misunderstood.
Hetzner is a German company so I find myself wondering if this is a British usage, or a mistranslation of the German word "tarif" that should be "rate"? (A common mistranslation category known as "false friends".)