Megatron's picture is not really cruel... besides... it is fictive of nature... it hasn;t happened nor will it ever happen (though in Transformers 3 he came very close!)...
The only reason I can think of WHY the WTS use illustrations like these is to put fear in the heart of us. I DO know it happened in the past... But hey: I am not making a drawing of people that are killed in a gaschamber either (even though it happened) ... I do not paint acts of raping or other sickness (even though these things occur even in historical point of view).
The fact that something is historical does not mean you have to paint it in a book that everyone WILL see... it is not even a historical PICTURE... it is a DRAWING and the thing with drawings is that you have to use your imagination! I can not understand why someone imagenes this into detail and puts it into a religious magazine/book that should have been encouraging! your Magazine is in a shop and I can choose to buy it or not... at a districtconvention you almost get it pressed into your stomach and you HAD to read it because it was given to you by the slave.
I, as a youngster at that time, was always very eager when a new publication came out (this one in 1990)... the fact that this image sticks in my brain is not because I love it... It is in my head because it shocked me to the core. And that is what they really want... to shock people this much so that they feel that every other movement is bad. Your magazine is not used for doctrine... but this lecture is.
See what I mean?