I will say this has not been our experience when visiting in August/September. My dd wears nothing but sneakers and after rainy days often ends up with blisters. We bring newspaper to stuff into her shoes in the room to help dry them out overnight and she has a different pair to wear the following day but wet sneakers are not fun at Disney.
When we've visited other times of the year when rain is less frequent it's not been a problem but depending on what time of the year OP visits, sneakers are not always the best option. Ask my teen - who will once again wear nothing but sneakers this Aug and we'll deal with the blisters when they arrive!