I know I'm being a little silly, but it is nice to know I'm not the only one who's ever felt this way. So much attention is paid to MZ twins that sometimes I feel like I don't really have "real" twins. It's hard to put it accurately into words.
I've not heard a whole lot of intra-MOM bickering over MZ vs. DZ...BUT man oh man have I heard the "are yours real natural ones?" spoken. Both by outsiders and within the community, which really makes me angry. I don't doubt that there will be some people that treat b/g twins because they're obviously DZ and of course that means that someone must have used IVF. (pretty ridiculous, since as far as I know there's a strong genetic tendancy for DZ twins and MZ twins are more likely to occur with people using ART than the general population--so there's another twin myth busted!)
It's kind of funny, when my boys were born, due to TTTS there was a 2 lb and 2 inch different between them (T at 6 lbs looked like a regular baby, D at 4 lbs definitely looked like a preemie, even though he wasn't really.) People would ask the question if they were twins, and then ask 'what kind', and then argue with me about it. (finally I just told people they were 3 weeks apart to see if they caught the joke, sadly most people didn't).
I think people have in their minds' eye and cultural mythology what twins will be like. I also think that unless we grew up with twin sibs or are twins ourselves most of US have those same ideas and since we know intimately that reality is often different from fantasy sometimes it's hard to deal with. I don't think that's petty or silly. It can be pretty painful, actually.
I wonder with all the 'twins dolls' out there, most of which tend to be b/g twins, if we won't have at some point or another a flip in what's popular/desired...since people will be thinking of their b/g twin dolls when they grew up and testing out b/g name combos. I don't recall any specificly twin dolls (I'm 34) so mostly when I was aware of twins it was because they were MZ or very alike-looking DZ. It'll be interesting to see what it's like, if any different, when our kids are parenting.