I'm not sure it pushes affiliates into anything unethical, if you were an ethical affiliate in the first place you would and should drop them like a hot potato, i was looking into adding them simply because ive played there and had no issues and they have a range of different slots which you cant find elswhere - specifically the blueprint slots.
But its simply not worth the headache, or spending the time and effort to try and establish some organic search presence with these new terms in place, for the big brands its hard enough to rank anywhere near the top for any range of keywords, so to set limits per month is an instant turn off for the small fry
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I do feel sorry for the affiliates that have already spent months and years promoting them to then have the rug literally pulled from under their feet though.