Depending on your length of stay, they only provide 2 things of coffee. We always go shopping to Winn Dixie for supplies for a week long stay but for only a few days I make sure to bring coffee and a few filters. No sense in buying a pack of filters for just a week.
A one bedroom will get four bath towels, two hand towels and four face cloths. A two bedroom will get twice that. You'll get clean towels every four days.
I'm pretty sure every single pool on WDW property has towels.
About the question as to if you should bring your own towels, I wouldn't waste the space in your luggage...if you are staying in a studio, you can wash/dry clothes/towels at any of the pools on OKW property. If you're staying in anything bigger than a studio, you have a washer/dryer right there in the room. Save that luggage space for souvenirs!!!