Spacing multiple mics creates a delay between each recording, adding to the stereo effect. It doesn't have quite the same sound as just panning a track left or right, do it's worth giving it a try. Because the stereo effect is influenced by the amount of delay between each track, you may need to experiment a bit with more or less space between the mics. Try it out at your next recording session.
You can read more details about how to influence the stereo effect with mic placement here: http://www.prosoundweb.com/article/better_recording_microphone_techniques_to_produce_warm_spacious_stereo/P3/