Why don't you just admit that Sweden is rigid and fucked up? Look at that melatonin thing: what you can buy totally free in the US and most of Europe needs a special license from a doctor here!
In the UK, you can import most prescription drugs provided that they're not scheduled (so no Vallium, amphetamine, pure opiates etc) and they're only for your personal use, but melatonin and Viagra are exceptions to that rule, and will be confiscated by customs unless you can produce a prescription; it seems they were singled out largely due to their popularity. That said, I was able to buy melatonin and viagra online without problems; it's just a matter of chance whether the package gets examined or not.
It's also very difficult here, as far as I'm aware, to get hold of a wide range of dangerous and interesting chemicals unless they're part of a product marketed for a specific purpose like drain cleaner, pool treatments, car batteries etc. UK pharmacies sell paracetamol and baby formula, not concentrated mineral acids. The difficulty of obtaining concentrated mineral acids in Sweden and the UK does at least have the benefit of protecting women, since some cultures have a bit of a sweet spot for acid attacks on women when those acids are easy to get hold of.