I sympathize with those who want feedback. Though believe me, when L&C fanfic first started in 1994 the stories were emailed out to 25 people who signed up to read fanfic and feedback was unheard of except for the occasional private email. Also, fic used to be posted only when it was finished as a whole story unit, not separate parts.
As for the feedback issue, there are some fans who don't give feedback until the whole story is posted because over the years they've been disappointed by authors who didn't finish their stories despite having lots of feedback for the individual parts. There is also the fact that this is an open message board in that you don't have to subscribe in order to read the post. If they're not subscribed, they can't post. I suspect most who are reading your stories fall into that category.
As "cain crazy" posted, she didn't realize that feedback was such a big deal to writers, and to be fair, it isn't a big deal to all authors, but for most it's nice to hear some encouragement. But don't forget the flipside of that coin. Sometimes readers won't leave feedback because they didn't really like the story and don't want to leave feedback that might hurt the author's feelings, or they felt the story was just so-so in their opinion and so didn't leave feedback either for the same reason.
Lastly, there are two sites that have Smallville fanfic forums and the sites are known more specifically for Smallville. There is Divine Intervention. The name stems from how Lois and Clark met on Smallville. You'll recall that Lois was driving down the road trying to find the Kent farm when lightning struck causing her to pull off the road and plow through a cornfield where she came upon a naked Clark Kent
You do have to register to read and post to their message board. http://loisclark.proboards.com/
There is also k-site. There are advertisements and popups on that board, but it has a large Smallville fanfic forum, and if you want to post Clana, Chlark, or any icky version other than the one true Clois pairing, you can. http://www.ksitetv.com/forums/forumdisplay.php?166-Smallville-Fan-Fiction