Yeah mom and I are going to do that on our upcoming trip. She'll probably head back to the resort, or to a hammock at the Poly, to read and veg while DD and I hit MK for some shows and rides. Mom likes the parks but she also likes her down time.
Likewise, I'll probably leave DD with mom and go get a massage at the GF or something.
Having a little alone time is always nice, because you get to do what you want to do for a few minutes without consulting with someone else.