Sorry, I misunderstood. I thought you were saturating the shoes with WATER from extensive walking in wet conditions. Hence my recommendation for waterproof footwear.
Greases and heavy wax treatments will protect leather from wetting. People at SF complain that they can also prevent the shine they want in dress shoes. Hence the recommendation to restrict their use, particularly greases, to work boots. If you are finding that your shoes are suffering from water exposure, then my first recommendation would be to find shoes that are better able to withstand water. Many shoes are made to be waterproof, and the leather is treated to achieve that goal. Much better than trying to retrofit water resistance to a shoe that was not made with particularly water robust leather.
For your purposes, I am not sure Allen Edmonds would solve your problem. It is not clear that the issue is low quality shoes. It sounds like it is using them in a way they were not intended. If you got AE's and routinely got them wet then they would deteriorate as well. You would be unhappy with the way they looked and the fact that you paid more money for them.
If lots of walking in wet conditions is the way your life is right now, then get walking shoes that are waterproof. Treat the uppers as the manufacturer recommends to maintain them. They should last.
Rotation: I was not joking about this. The inside of shoes accumulate moisture during the day, even without walking in the rain. This is a great environment for microbe growth. Resting the shoes for 1-2 days between each wear gives them a chance to dry out. This does not completely prevent mold growth, but it reduces it. Wearing the same pair of shoes day in and day out is asking for trouble. If you rotate your shoes then you are far less likely to have the problems I described. I don't know whether the exterior of the shoes will benefit from resting, assuming they never got wet in the first place, but the inside certainly will.