Aurora: nearly all webcomics are "intended" for print as a secondary market. But the point is: if you are creating new work that is going to be viewed primarily on the screen, do not use storytelling techniques that only work in print; those techniques will fail.
Webcomic creators need to concern themselves first with how their work satisfies the first readers--the people who may read their work online. Because if they don't satisfy those readers, there will be no print collections.
I would say that if one has his or her heart set--I mean dead set--on using tools like double-page spreads, then the real issue is that they should be trying to finance a self-published print-only book. People still do this too, and with Kickstarter, it's become more and more likely for independent creators to set forth and fund their projects.
DISCLAIMER: It's mine, I made it, feel free to regard this as shameless. Flay me as necessary. Also? apologies for resurrecting a thread from months ago.
But I'll weigh in on the format issues. In this case, I started the project intending it for print. For a variety of reasons, I discovered it would be more sensible to put it on teh inter-nets. So I needed a way to display the 2-page spreads, and here we are. I acknowledge the weaknesses - primarily that the images need to be so large (to preserve text readability) that it may be a more awkward experience for a reader with a smaller viewport. I still would like the book to exist on paper - I prefer it to reading from the screen - but I also want to remove the barriers of cost and availability between a reader and this comic.
I am all for comics that are specifically web-created and thus web-exclusive. Use the medium to it's best advantage. Like this. If I were to come up with a concept that exploited the strengths you get from the digital medium, hey - why not? Let's make that.
But as long as a maker wants to end up with a dead-tree version, you'll have to acknowledge that format's limitations at some point.
@darrylayo - I'm having trouble thinking of techniques that would work only in print, but not online. Perhaps the 2-page spread, if one's site isn't built for it. What am I missing?