If they can lead the same life as straight couples, then what is the point in denying them the possibility to marry?
Apart from their sexual desires, "they" are exactly the same as straight couples.
There is no justification for this particular case of discrimination.
To put it Fragony-style : non-discrimination>traditions. In other words: if tradition leads to blatant legal discrimination without justification, then we should get rid of the tradition.
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