This was stated in a marketing podcast.  It is a nice mash up of “getting a leg up on someone”  (an advantage over someone) and possibly “putting a best foot forward” (giving it your best).  However, Marcia Johnston, who spotted this one, also mentioned that “the phrasing might imply ‘having people underfoot’, although that meaning is more to do with other people creating a nuisance than with having an advantage over people.”  She also thought the concept of people you meet (step on?) while climbing the ladder of success might be in the mental mix.  I think “getting off on the right foot” (to begin something that is likely to succeed) may also be in play here, as it is consistent with the message the speaker is trying to convey.  In any event, feet and legs get tangled up in this one for sure!  A big thanks to Marcia for sending this one on and for her deconstructing insight.