This is a leaflet I saw in the ISKCON temple in Mumbai. Now, there is a huge mistake in this argument. The huge mistake is in mixing up two kinds of “why” questions:
1) The first why question demands a descriptive explanation why something happened in the world. For these kind of why question we ALWAYS demand a rational explanation. This also goes for phenomena, like love. Maybe these kind of explanations are not yet very complete, but they are and have to be rational. So, for example, if a girl falls love with a boy, the explanation might be that the boy is handsome, he is strong, he is talented, and this makes a good impression on the girl. Or vice versa. And they spent good time with each other, had nice experiences. Moreover, there are hormones, pheromones, there is an evolutionary basis of why love is important in the life of the homo sapiens communities, and so on. This might be a pretty good and rational expression. For this question an irrational answer is not good: like: “the girl fall in love with the boy, because there are elections in India”. This is nonsense, not an explanation. So here, there are 2 kinds of answer:
a) A rational, that is a good answer.
b) An irrational, that is a bad answer.
2) On the other hand, there is a “why” question about the motivations. Why we do thing, what are our motivations. Now, these motivation may be:
a) Rational. Like the boy married the girl (or vice versa), because the girl is really a very good choice.
b) Arational: the boy married the girl or vice versa, because the boy liked the girl. This does not seem an extraordinarily best choice, but it is also not a very irrational choice, it is simply a subjective choice, so why not?
c) Irrational: the boy married the girl, because he loved her, despite, we know, that the girl is a very bad choice for the boy.
Now, note that while c) might be the case for the question 2), i.e. the motivation of the boy seems to be very irrational, still, we might have a completely rational explanation in the sense of 1). we might know completely well, why the boy behaves so irrational, for example, the girl is very pretty, the hormones of the boy run havoc, and therefore it happened.
Now, going back to the question of the color of Krishna. This one mainly not a question of type 2). Our objection is not about why Krishna did this. The main question is not his motivations. The main question is how it was possible for him to be blue. How did that happen? And this is a “why” question of type 1). And since there is no rational explanation for this, we do not believe in these nonsense, we think rather, it is a fairy tale. So, the parallel with love is utterly mistaken here, the Krishna-Church gave here a very stupid answer. Like usually any religion, this is also very stupid.