I'm still not entirely sure how this "cartel" works.
Shipper walks into agents office, " How much can you send this for?
"2.00 a kilo"
Agent goes to an airline, "How much can you ship this for?
"1.20 a kilo plus fuel surcharge and handling etc", and then repeats that process and will suceed unless there is a capacity issue.
Just because you can match the price of a competiter does not make it a cartel.
Why are petrol prices the same no matter which garage you go to?
And surely IATA must be done as well, as IATA rates are fixed, so if that is not a cartel, nothing ever will be, all airlines in the world to be sued due to this.