I too would like to find out a really official answer on this question, and this thread is as good as anyplace to put it.
Incidentally what would happen if you say you "changed your mind" and want to make a U-turn rather than pay?
Would the toll taker just tell you to bear right at the fork just after the toll plaza and go left at the next light where you can, which will make the U-turn?? If so, once you passed the toll plaza in this fashion you are home free to go to the resort.
More Disney tips:
http://members.aol.com/ajaynejr/disney.htm
9/65
Disneyland
3/75 *World Inn (now Doubletree Club)
4/85 *Kon-Tiki (now Econolodge Hawaiian)
'80s Disneyland once or twice
7/94 Dixie Landings (now Port Orleans Riverside)
9/97 All Star Music
11/98 ASMu & first premium annual pass
12/98 *Knights Inn on 192
9/99 All Star Movies
12/00 All Star Sports & PAP#2
9/01 ASSp
11/01 ASSp
1/03 *Motel 6 & ASSp & PAP#3
11/03 Pop Century planned
* off site