But there's a difference. Omnimovers are continuously loading. Their lines would never get longer than 30 minutes if there was no fastpass.
Omnimovers should not have fastpass. Period.
Wrong. First off, Haunted Mansion loads in groups into the Stretch Room, but we'll ignore that.
Omnimovers don't get long lines because they have a large capacity, not because they are continuously loading.
If an attraction dispatches 2 guests every 2 seconds (For the sake of this argument we'll call this attraction an omnimover), that attraction has a capacity of 1800 guests per hour. If 0 people are in line for that attraction at the beginning of the hour, and 2700 people line up for that attraction at consistent intervals (say 2 guests every 1.5 seconds), then that attraction will have a wait of 1/2 an hour at the end of that hour. 1800 people will have been on the ride, and 900 more will be waiting in line.
If another attraction dispatches 24 guests every 30 seconds (For the sake of this argument we'll call this attraction Kilimanjaro Safaris), that attraction has a capacity of 2880 guests per hour. If 0 people are in line for that attraction at the beginning of the hour, and 2700 people line up for that attraction at consistent intervals (say 2 guests every 1.5 seconds), then that attraction won't have a wait at the end of the hour. All 2700 people will have been on the ride, and conceivably an additional 180 guests could have gotten on the ride without more than a 30 second wait).
But they aren't continuously loading. Their lines stop and start, meaning that no matter what there's going to be back ups that omni rides wouldn't have.
Also, Safaris shouldn't have fastpass, just as Jungle Cruise shouldn't.
See above. Fastpass lengthens standby lines - there's no question there, but if used correctly it helps guests see more attractions per day. The reason why this is true, is because not everyone can (or is willing to) use it at maximum efficiency.
If you're arguing that Jungle Cruise, Safaris, and any Omnimover shouldn't have Fastpass, what should have Fastpass? If your argument is that it should be removed entirely than it's a different argument altogether.