In reply to Rob Greenwood - UKClimbing:
I'm pretty sure they're aware, but fighting this is Sisyphean as having one taken down means three new ones pop up.
My employer, another household outdoor brand, has taken the step to put an authorised reseller finder on the website.
The rules of retail means that basically anything sold for more than 70% off is very likely to be fake - and 70% off is already outrageous and really only happens with stuff that's long out of production and with off sizes such as men's XXS or women's XXL. Oversimplifying a bit here but if you're selling it for less than 50% of RRP you're basically burning money.
Other tell-tale signs are weird language or slightly iffy grammar, using generic disclaimer texts that mention products the brand doesn't even make, only having creditcard payment options, and having high discounts on current-season products in full size ranges.