I see snap pads a bit differently in that they displace weight over a slightly larger area. I just don’t want the legs fully extended when I don’t need the displacement. I honestly don’t know the answer as to whether or not it matters as long as it is centered. I guess that is the question I ultimately have. I’m going to probably try Bryan’s solution.
I agree I think full extension or amount of extension a bigger issue than displacing the weight. The force of the weight is transferred straight down the leg. Now I agree that if the pad is wider than my 6x6 block you may not get full displacement but I don't consider that critical.
However maybe where we disagree is that the pad actually helps with displacement. The pad is a flexible rubber. I can't see how that rubber pad can add any significant support to the steel foot of the jack leg.
On uneven ground the pad helps the legs sit flatter against the ground and allow for better support and weight transfer. But this is really only for lab or paper analysis only. In the real world you can park on gravel without any issues without snap pads.
If the ground is really soft and the grass is wet or muddy from a heavy rain, snap pads are not going to save you. But boards beneath your jack feet will.
Ultimately the snap pads protect the feet from scratching and denting and ground the foot lands on. But I don't believe they provide any significant structural support
In the end I don't think snap pads are really necessary. Sure they are nice to have but not critical. I consider blocks on the front legs much more critical to stability by reducing the extension of the legs vs. snap pads that may reduce extension by 1/2".
I camped 10 years with my last 5'er with no snap pads without issue. The only reason I have them now is that I have been to a couple of CG's that require them. (its a rule but not really enforced). There are also cheaper knock offs now available that are reasonably priced vs. the official snap pads.