Are they really though? I know a lot of some people, who would consider themselves "well meaning" (fair, honest, just, whatever) and they totally do this all the time.

When you combine the actually bad people with those people, isn't 30-40% of the population constantly fucking with the system?

See also: Democracy. App store reviews. The soundscape. Climate change. Etc.

I'd guess about 99% are basically ok with reviews. The trouble is if only 5% of those bother reviewing and 1% of the bad ones post a bunch of fakes.

Incidentally I use argos.co.uk a bit and have found the reviews there always ok so far. Maybe Argos polices it or that crowd doesn't bother faking? It's different from Amazon in that there are no independent sellers so the only people motivated to fake would be the manufacturers.

I think it only becomes a problem when the system gets big enough. If there's 20 different online storefronts, it's a lot more time and effort to game the reviews on all of them, than if there's only Amazon.

As you say, that breaks down the second anyone decides to use fakes.