You'll always get more life and comfort out of a shoe with a hard sole and replaceable insoles than a foam rubber sole like on most walking/running shoes. This isn't the fault of running shoes, they're just optimized for minimal weight and maximum shock absorption. If you're mostly standing and walking short distances (like factory and warehouse work), support and cushioning are what really matters.

I used to have a job that involved a lot of standing on concrete for 10-12 hours a day. I'd go through a pair of boots about every 2 years, and insoles about every 6-12 months. That said, the insoles I used were about $50 on their own, so on average I was spending about $175 a year on footwear (1 pair of $200 boots and 3 pairs of $50 insoles every 2 years).

If you're not in an environment that destroys footwear, a good leather work shoe like redwing should last a very long time, and you can probably get about a year out of insoles.