Color is more complicated to apply in every way. If you want to make your comic look good, it would help to learn a bit of color theory. Awful coloring could really take away from the art and the story, but beautiful coloring can enhance it tenfold. And 'beautiful' doesn't have to mean complicated, either—a simple 2 or 3 color palette can do wonders to establish mood and setting. So there's all that to think about, not to mention the printing options that @Spitfire mentioned.
I don't view greyscale as neither inherently boring nor easier, but if you've got the hang of your light logic it's much faster. Without colors, you'll have to rely very strongly on composition and contrast in order to make your panels appealing. This can force artists to become better at drafting, since they have to do more with less. Ideally you should be focusing on composition and contrast anyway, but when you have color, it's easier to get away without doing so. Of course, printing greyscale is much cheaper, too.
I personally chose to do full color for my comic because I felt that it was an area I wanted to improve, and back when I started the comic, it was just for fun and practice. Since then I do feel like my skills in coloring and using Photoshop have improved exponentially, so even though I actually hated color to start (and constantly kicked myself for choosing to do a full-color comic...), I don't regret the decision now.