All prices are in USD
Anyway, I waded into the absolutely absurd world of hazmat shipping and -- dear God man, mostly I discovered that a lot of the things I buy online can't legally be shipped. I'm just gonna take NR's word for it on the 45 USD per 4 litres for 60mg/ml+ nicotine, but which they seem to wave when you break into free shipping at 50 USD (this worked with just the small bottle costing like 25USD shipping, but the 1 litre by itself is free shipping)
As for the 48mg -- a 60ml bottle came out to 3.39 shipping -- 16.45 for a liter. And this is true for just VG as well.
But I put 150ml 48mg and 5 bottles of 1oz flavour for a total shipping of 10.55 -- but here's where things get interesting, add a no-fly flavour of any kind and it goes up to 25.56 -- swapping for a second no-fly flavour doesn't increase it.
Oh, and 60mg/ml 150ml of nicotine is 25.56 shipping as well, with or without a hazmat flavour, because it's just anything that is hazmat that does this.
So, there are actually a couple things that could be happening here:
A: You got charged for hazmat nicotine due to a bug and it is either fixed now or not a guranteed bug.
B: You got charged for hazmat flavour -- but given that NR already said that it was A, from what you said, I'm gonna assume it was A.
I couldn't replicate 31USD -- but that's likely because of our locations.
Result: If ordering from someone who follows FedEx regulations in the US -- go for the free shipping, because the shipping cost is gonna be as much or more than the purchase price otherwise (and basically end up costing over NR's 50 USD barrier for free shipping anyway).
So the shipping gouge is real, but not what's happening with Nicotine River.