Personally, I enjoy seeing people wearing their medals after events, even if it's a week later. I've brought a number of extended family down to WDW for RunDisney events, and several of them were quite shocked and inspired by the "regular runners", as my sister-in-law called them, who were sporting medals. Several relatives have always felt a little uncomfortable participating in races, as they're not the "stereotypical runner", ultra-lean and able to run 5:00 miles for hours on end. I've told them for years running is for EVERYBODY, but when they saw the diverse crowds at RunDisney events, they really felt like they could belong as well without having to feel slow or unwelcome. So when you folks wear those medals, you're saying not only "I DID IT!" but also "YOU CAN TOO!" and you're inspiring people to live healthier lives and achieve goals they might've thought were impossible for them.
Happy running, all.