I would agree continuity is a problem as it scares away new readers
If they're not intelligent to buy the preceding trade, or look up the character on wikipedia, than f--k them. I'm not a babysitter in the shop, and I'm certainly not a history teacher.
Kid comes into the shop and loudly - asks who the Red Hulk is. I'm paraphrasing a little - but this is the basic convo
Kid: So, who's the Red Hulk
-Actually Busy Dave: It's part of the story, they haven't said yet.
Kid: But you know, don't you, I mean if you work here, you know
-Busy with actual customer Dave: No, I don't, actually - I have my suspicions, but, thats all they are...
-Other customer who is actually buying something: You said it was Betty Ross
-Me: I said it was Jeph Loeb, it didn't have to make sense.
-Kid who is still here: So why don't they tell you who it is
-Mildly irritated Dave: Because its one of the standards of fiction: They've set up a mystery, and are keeping people in suspense until they choose to reveal it.
-Kid actually picks up Red Hulk ~2 and puts it on the counter: How much is this then?
-Pleased to be actually working Dave" Five Euro ten, thanks.
-Kid: A fiver? for that....f--k off, i'm not paying a fiver for that.
Kid goes off, and presumably agrees to spend seventy quid on some videogame he'll be done with in a week, while i spend 10 minutes of my life rearranging the comics he decided to pick up off the shelf and put back anywhere he felt like.