The only place I have every felt under-dressed was Cinderella's Royal Table. We were in matching tee-shirts for our daughters birthday dinner. We had been at the park since rope drop at 9am and it was now 7pm. I was a hot, sticky mess, had been soaked numerous times on various rides and had my hair pushed back with a hairband. The people at the surrounding tables had obviously not spent the day in the park and just arrived at MK for their dinner. Perfectly turned out in pretty summer dresses for the ladies and long pants and shirts for the men. More than a few glances were cast our way that night!
Then, on the other side of the coin..... we were dressed in our wedding attire (see avatar) at Yachtsman Steakhouse and the family next to us rolled up straight out of the pool with children wrapped in towels, who proceeded to spend most of the meal sat on the floor under the table.