Mismatched helper springs

[Camper Special]

I've been wondering about the helper springs on my 65 Custom Camper, drivers side has 5 leafs & passenger side only 3 leafs? I'm the 3rd owner and to the best of my knowledge they were dealer installed. Anyone seen this before? I'm thinking it is a dealer screw up, but maybe there is some graduated loading theory as this did come with a rather large slide in camper and posi rearend? (sorry right side pic is blurry but you can still see difference)