From an engineering perspective the front and rear steadies aren't quite the same on my caravan (I don't know if there's much variation between different caravans). The rear steadies are fixed to the chassis thus the load is spread over the length of the chassis (between the axle and rear steadies). The front steadies are fixed to the wooden floor. With the jockey wheel raised the front steadies are supporting the wooden floor which is then supporting the front chassis / A frame / hitch. With the jockey wheel down the chassis is supported by the jockey wheel which then supports the floor (in addition to the steadies). I don't know how much difference this makes but I always leave the jockey wheel down when pitched as I can't see any advantage in going to the additional effort of raising it.
There is no problem! It's a question of personal choice whether to leave the JW up or down when pitched on site.
When arriving on site, the caravan should be levelled side to side by using ramps (and chocks) under the lowest road wheels, then The JW should be used to level the caravan for and aft, and the steadies then deployed to "stabilise" the position of the sited caravan.
The
standard ALKO short steady has a designed mass capacity of 800Kg , so the steadies are more than capable of carrying the likely load of the corner of any normal touring caravan even with occupants moving around or seated at one end of a caravan, without the aide of the JW.
From a consumers point of view, if the steadies provided by the manufacture are not sufficiently strong enough or installed incorrectly to "steady" (not lift) a caravan then the steadies are not fit for purpose, and the seller could be held responsible under consumer law.
From an engineering perspective, it is wise to ensure all means of caravan support is suited to the task, but there is no harm in using the JW as a belt and braces to support the caravan.