In theory, no. In reality, maybe.
Technically, valet parking is only free at the
DVC Resorts, but...
One valet tag from any WDW resort is good for the whole day, at all resorts. Thus, if you have a tag from a DVC Resort, the valet parking for the rest of the day, at all resorts is included.
That's sort of a back door approach to free valet parking. I always point out to the valet that I didn't pay for my valet tag from the DVC resort, but they always insist it's taken care of.
Clear as mud?
PS- Don't forget about tipping!
MG