Not a gimmick from an engineering perspective. The difference between hub versus lug centric has to do with how well the assembly withstands different directional forces. Lug nuts are designed to handle lateral forces that push the wheel away from the mounting plate. The forces that the hub and center bore connection are designed to withstand – the weight of the trailer forcing downward and impacts forcing upward – are at right angles to the forces that the lugnuts are designed to withstand. Lugs will be sheared off at a lower impact than hub centric failures.
"Good judgement comes from experience. Experience comes from bad judgment."
Sirs Gawain & Galahad
Air #48582, S/SO #003, WBCCI #4584