What's odd about buying your phone outright? When you buy a subsidized phone, it's a loan, and you pay a lot in interest per month for this loan. Buying a $750 iPhone outright might be a lot of money upfront, but when you have a plan that doesn't have a subsidy cost per month built-in, you actually save a LOT of money over the two years you have the phone. Plus, since everyone with a smartphone in a particular company (Verizon, etc.) is forced to pay the same subsidy per month anyway, regardless of how much their phone costs, the ones who get the cheaper phones end up losing out the most. And the worst part about the subsidy? Even after two years when you have "paid it off," they still include the subsidy in your bill every month. So for people who get a two-year contract subsidized phone and keep it longer than two years, it's the equivalent of paying off your mortage but having to keep sending in monthly payments anyway.
I'm not saying that everyone in the US should be forced to pay outright for their phones; there should definitely be a choice. I'm just saying that if you have the money available, it's ALWAYS cheaper in the long-run to buy your phone outright, even if it's a really expensive one like the iPhone.