Firstly, the position of the unit in a building is often a factor in establishing unit entitlements (the basis on which levies are calculated). The higher you are in the building, chances are, the greater your levies.
There is no legal basis that I know of for charging everyone exactly the same amount (although this may be different in QLD).
I know of buildings with no lifts that contribute to adjoining parts of the same strata that do have lifts (townhouses next to high rises, for instance).
But the remedy for this is to have the unit entitlements adjusted so that the non-lift users pay less and this can be done by application to the CTTT or its state equivalent
Finally, if this work isn’t covered by warranty then it means the sinking fund has been neglected. It’s swings and roundabouts – if you don’t put the money away, it will eventually come back to bite you on the bum.