Interesting comment. I think the recent spate of 112+ degree weeks in LV, setting records, combined with more than 60% of Americans being obese, combined with car rentals being pricey, combined with parking fees, all coalesce into people not walking, not driving, and therefore not visiting properties outside the center strip. I think people can still handle the full-block-walk once a visit, down to Wynn or up to MGM, but that's about it. If you're center strip, as most people are, that's where you'll drop anchor.
The monorail becomes a key variable in whether people visit up or down the strip at all. I have no idea what percent of visitors actually use it.