I'll give "Superpowers", but they had a whole bunch of JL toylines in the mid 90's, including videogames and shit. They had one for JL Task Force, for fuck's sake! This was more than a decade ago, hardly "recent years".
How would you know if they got decent advertising or not, if you're not the target audience for these toys? Of course we've seen the ads in comics, but other than that, they would be shown outside our "jurisdiction"; that is, during kiddie cartoons and stuff.
And don't forget the JL underpants, birthday napkins, monopoly games and such, which also play a big role in expanding awareness of the concept. An awareness that I believe was already well expanded to begin with, thanks to the magic of culture that goes "POP!".
About the Transformers: I honestly don't remember watching ads for those toys while growing up, except for Beast Wars, and as I said they never called them "Transformers" outside the show (at least that's what I recall). I'm not saying there's absolutely no fucking chance in the world that the Transformers weren't constantly advertised: I'm saying, like most toys, these ads are sector-specific.
