It's one of the features of Ibuprofen that you can take it at those levels without killing yourself. Most people don't, but some people do - sometimes because doctors tell them to.

This makes it different to Paracetamol, where you only have to double or triple the standard dose to cause temporary liver damage, and increasing it only slightly further puts you in danger of death.

> it's not a dose people will commonly take in their "day to day" activities

A lot of people who exercise multiple times a week take "Vitamin I" every day. So do people who have frequent headaches, back or joint pain, etc. I probably came close to these levels during a bout of plantar fasciitis, though I've since switched to naproxen in such cases. It might not be common in your immediate circle, but in the broader world it's not rare enough to raise any eyebrows.

I went through a period of heavy physical activity without good equipment, which caused quite bad shin splints. My doctor prescribed precisely this dose, along with some physiotherapy. I think it's quite common for inflammatory problems like that.

I disagree. People regularily take 800mg of ibuprophen for regular/tension/miagrane headaches. These can be quite regular and chronic occurances.

When I would visit military doctors, they would prescribe 1g pills like they were a panacea.