For PHM all the Disney hotels are host hotels. All that means is that they will have transportation (bus or monrail) to the races as well as transportation to the Expo. People who have very specific preferences or DVC members who have limited selection book early. If you book now to get something specific (like a boardwalk view) and a better hotel deal comes out later you can call and change it. The PHM weekend also coincides with New England states winter breaks, it's at the end of some states and start of the others. I believe parts of NY and NJ as well. Those who make a week out of the Presidents' Day holiday also will be there still, and this year Mardi Gras is also part of the vacation mix

So if you have something you really want, I'd book it and hope for a discount later. I booked my DVC on the very first day I could. But at 7 months out I'll be trying to change it to another resort.
Hmmm after race snacks. I ran straight to self treatment for ice wraps, so I know I got a banana and they gave a box with craisins, chocolate covered blueberries, hummus, popchips and a bar of some sort. I think there might have been bagels. There was water and powerade. I mostly cared about getting ice send wrapping my knee, and then finding my family, so my memory is a bit foggy I think.
How to fit the race into your schedule really depends on your vacation style. I arrived Wednesday and stayed to Tuesday. I thought it was great. We had plenty of park time and the races are over early allowing you to get back to vacation mode for the rest of the day. My only requirement to my family was pool time - which translated to me lying on a lounge chair - each late afternoon, and early (5:30-545) dinners. The 3:15 wake up alarm is early

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