I just asked my husband why men do this, (he is also guilty of the whole "i just took a poop, wanna see it?" thing) and he says:
"damn, it's because you're my wife! Don't you want to know? What if I'm hospitalized and the doctor needs to know about my bowel's functions!"
He then proceeded to ask me about my bowel's functions "just in case".
Op, men don't really say a whole lot of "I Love you"s. Men say "Come and see if you can handle smelling my fart."
It's um.... affection?