Yes, 1 cu/ft of resin has 32,000 grains capacity (closer to 30,000 grains in actual practice).
As the average water consumption rate is 60 - 65 gallons per person/day, and as you said you are a couple (2 ppl), your 2000 gallon regeneration setting should mean 1 regeneration about every 2 weeks. (2000 gals ÷ 130 gals/day = 15.3 days).
I am not familiar with the amount of Potassium needed to regenerate 16000 grains (as confirmed by Reach) but even at a high salt setting of 15lbs per regeneration, that should equal only 30lbs/month which is substantially less than the 80lbs/month you stated.
Resin utilized for water softening is most efficiently regenerated with Sodium Chloride (salt). Regenerating the entire 30,000 grain capacity of your softener would require 15lbs of salt but that would be an inefficient setting as it would equal only 2000 grains per pound of salt.
More efficient salt consumption may be obtained by programming the regeneration to occur sooner and by re-adjusting the amount of water entering the brine tank. For example, 8lbs of salt can regenerate 24,000 grains and 6lbs of salt can regenerate 20,000 grains representing 3000 grains/lb and 3333 grains/lb respectively. Each gallon of water entering the brine tank will dissolve 3lbs of salt.
Although salt is more efficient and common, you have instead chosen to use Potassium as you had done with your old softener. As you were happy with the results from your old softener, there is no reason you can't achieve comparable results with your new unit. Though the installer said there is nothing wrong with the current programming, he may have programmed for consistent results regardless of temperature (see Dittohead's article) and not for efficiency.
Data still required includes the brine tank refill time currently programmed. It appears you may need to count the pins installed on the refill section of the program wheel as each pin represents 2 minutes at 0.5 gal/min = ? Gallons brine water. Knowing the brine refill amount will permit the amount of Potassium consumed per regeneration to be calculated.
Once you provide the refill time, that along with the other info already provided, will assist Dittohead or another forum participant who has Potassium experience, with the background data to better assist you. Also useful would be a description of the environment where the softener is located as well as your incoming water temperature (as per Dittohead's article).