I think you truly could do without:
Here's "my Disney experience"
I always listened to music as I ran - always 1 earphone only!).
So much so, that I would not even consider an event that forbid them!
I knew I could manage 10k or less if I had to w/ no music, but a half? and a full? my first Marathon? I was pretty sure I'd need my own music to get me thru! I was so nervous that my ipod shuffle might run out of power, I had even brought t
But, I gotta tell you, for all the Dopey, my music truly was not needed!
There was that much going on around me, just from the runners alone, that I never needed it.
I started running using music, and I find it helps me thru any hard spots, but at Disney, I fed off the energy and people around me.
And there's a lot of random yet great conversations you can have with great people if you all can hear each other!
On a sidenote, OP, is the reason that you can't use earbuds because they fall out or aren't comfortable?
I found most earphones painful, or else they'd fall out every time I accidently nudged the cord. I went searching the internet for a solution, and found a company online selling "One Good Ear" and "Short Buds" and " BUDLOKS"
The budloks are a bit of moulded silicone that slips wee earbuds & then hook along the next part of your ear! Putting on/taking off sunglasses didn't interfere with them, and I didn't need to worry about the earbud snugly fitting in my ear.
If this sounds like it might help, just search those keywords.