The system is set up in such a way that you cannot use a base ticket that does not have the hopper option in more than one major park (AK, EC, MGM, MK) on one day. Also, either a base or hopper cannot be used in a minor park (BB, DQ, PI, TL, WWS) without the Water Parks Fun and More option.
If you have been to one park and attempt to use your ticket in another park on the same day, when you put it in the turnstile several things will happen.
1. The display on the Guest side will show "ACCESS DENIED".
2. The turnstile will not unlock.
3. The two line display on the Greeter side will show information about the ticket's entitlements on the top line, and on the lower line it will say "CROSSOVER NOT PERMITTED". (If a minor park without WPF&M it will say "ACCESS NOT PERMITTED".)
If the Greeter wishes, by pushing a button he can see exactly when and where the ticket was used last.
Depending on the Greeter, and how crowded it is, you will either be told your options at that time or told to go to either Guest Relations or any ticket window for further explanation.
If I have the time, or when I am in a booth, I will explain the options as follows:
1. Upgrade the ticket to a hopper (currently $45 whether one day or ten day and adult or child).
2. Go back to original park, as unlimited same day re-entry is permitted.
3. Just go away and don't bother me (actually I wouldn't say that).
If at a Water Park I would explain that for $50 you could upgrade a ticket to include between 3 and 6 minor park entries, depending on the number of base days on the ticket. Or if you plan on only one day at a minor park that you purchase one-day tickets (currently $36 adult, $30 child 3-9).
Since Disney charges only $2 per additional day over five, $45 for a hopper and $50 for WPF&M, it does not make economic sense for Disney to allow use of an extra day on a non-hopping ticket to hop.