Telika: Uh. Well, I did learn to read with my parents, in comic books (european ones, like the Smurfs, Tintin, Lucky Luke, Asterix, etc). So, I am mostly surprised that it looks surprising. My dad, though, when he was a kid, had to read comics in secret (even Tintin), because it was considered to be delinquency, or brain-damaging, or whatever. But, again, at his epoch, comics were actually quite new.
I wonder if comics have a different status in the USA. And I wonder if the dominant content (superhero piff wham k-pow) has to do with that, classic european comics being generally more "wise" and "peaceful". Maybe both universes had a subtly different approach to educative contents, leading to different levels of legitimacy ?
You can't quite compare the US with the whole of "European culture", as for example in France comics are in much higher regard than in Germany. Over there they've long been considered "le neuvième art", while over here until less than a decade ago, comics were still marginalized and treated as either geeky or childrens' stuff in general, even if some comics like Asterix were more widely accepted than others.
Also, I think there's nothing wrong with teaching the kids how to read via comics, but often the underlying hope of the adults is that the kids will move on to "real" literature at some point and outgrow the comics, as if comics were a lesser form of literature and not a completely different medium or even art per se. That's why comics for adults are now promoted as "graphic novels" over here, to enoble them by likening them to high brow literature. My guess is that most French comic artists would find that new term pretty silly (I'm not necessarily saying it is, but the French don't really have a need for it, as its main purpose is to enhance the image of comics for a pre-judiced audience that doesn't accept them as an art in its own right yet).
Anyway, as the examples of Sogi-Ya and you show, in the end it all comes down to how you were raised. My dad was never really interested in comics (at least not beyond his youth) and he often commented on me reading them as if it was something immature to do, especially when I grew older (and regardless of the comics' actual quality and themes). I have uncles his same age though who were really into Asterix and Mickey Mouse even as adults and I often borrowed stuff from them when I was a kid.
EDIT: I do believe though that the perceived predominance of "piff wham k-pow" superhero, pulp and action comics in the US that you mention had an influence on the image of comics in Germany and made it easier for elitists to disrespect them as an art form, as I think back in the 50s or so there were certain tendencies to belittle American culture, maybe in order to deal with the "humiliation" of being defeated, occupied and educated by the US - although that's just a wild guess, since similar tendencies can be found all over Europe even to this day.