Hiya, Lisa, and welcome to
planDisney! Thank you so much for bringing us your question.
I spoke with a very friendly Cast Member and, unfortunately, she did confirm that complimentary towels at the
Walt Disney World Water Parks are only available to
Disney Resorts Collection hotels. To answer your question, the difference between the Swan and Dolphin hotels and Disney hotels is that the Swan and Dolphin qualify only as Good Neighbor Hotels. This means that they have the Disney stamp of approval when it comes to quality, comfort, and value, but they are not owned and operated by Disney.
If you'd like to rent towels during your visit to the Water Parks, you'll need to pay a small nominal fee per towel. But if you'd rather avoid spending any extra money, you're also more than welcome to bring your own towels from home. And since we're talking about items we should bring to the Water Parks with us, I encourage you to bring some sunscreen, sunglasses, and a hat. Also, please don't forget to stay hydrated! Being around so much water can sometimes make us forget that we need to drink up, so make sure to actually do it.
I hope this helps, Lisa! If you have any other questions, you know where to find us. Have a magical day!
Warm hugs,
Ana Paula