Toss up. Going out, I'd go through lobby. You never know when you're going to get ailse blockers - esp if you have a stroller in your group. Returning, it may be better to cut through makret if you are dying to get in to AC or heat sooner. On the other hand, I think you also run a risk upon returning of getting stuck behind someone in the gift shop. It may happen going through lobby that you get stuck behind someone with luggage, but you have more opportunity to go around them.