Let me ask you why you think other airlines all have the FOs do the walkaround. Are a large amount of FOs new to Allegiant and unfamiliar with all of the errors possible in both the logbook and paperwork? Would they be more likely to see an issue with the physical aircraft on a walkaround vs hidden on the third page of a flight release?

I don't always do walkarounds and I am a captain. In my own opinion it is usually due to all the factors mentioned above and allocating the proper resources than throwing my weight around.