I like drawing feet more than I like drawing hands, but I draw hands a hell of a lot more than feet in my comic. In fact most pictures I draw outside of the comic are full body images, because I just have a habit of wanting to finish drawing the whole body. (It's actually a habit I have to actively force/remind myself to break because it's often not good composition wise depending on the effect / focal point your going for in a picture) When it comes to comics though the majority of panels are not going to require a full body drawing.
It's not an issue of avoiding drawing them, it's an issue of people usually wearing shoes/socks (depending on if you literally mean feet or are just talking about the foot area in general) and 'why the **** would feet be in this panel??'
Because of the nature of narrative focus and what you want your readers to be looking at / perceiving the image, feet usually only show up extreme zoom outs, angled perspective poses, very specific poses that take the feet off the floor and bring them closer to the upper body, and deliberate close ups. A lot of these things something you don't want to saturate your comic with when they're not needed else your scene when you want it to show up will lose it's dynamic visual impact. Also keep in mind that feet are character trait, and not even all panels are going to have characters in them.
This happens because comics are driven by a combination of dialog, visual actions and ques, and because feet are not a tool humans often utilize to convey normal person to person conversation and expression like faces or hands, it's natural that you're going to see them less and pretty much only when it's necessary to create a panel featuring the circumstances mentioned above. There's not shoe/feet quota artists are trying to fill, or some underlying fear of drawing feet artists are unaware they have (for the most part anyway, some artists may very well do this) it's just that well flowing dialog, conversations and events that the readers can easily follow on the pages and panels without getting confused with what happening or going on that is our top concern (or at least is one of the things that should be)
What I DO find weird and often off putting is when artists avoid drawing hands and actively try to keep them out of the panels.