The "dummies" reasoning seems pretty sound. But I've got two comments on the "costs" which have to be factored in to the "total cost" and decide whether "cheap customers really do cost more":
1) Costs should really be calculated relative to your margins. I.e. I would hazard a guess (due to economies of scale) your cheapest price plan would have higher margins than your larger price plans.
2) The actual cost of support issues - I've found (running xp-dev.com, which mind you, should really not have that many "dummies") that while the cheapest customers do submit more support requests, these requests tend to take much quicker in resolving, than say the larger customers.
So, I think its not as easy as saying "Cheap customers cost more". I think its better to say "cheap customers request more support"
1) Costs should really be calculated relative to your margins. I.e. I would hazard a guess (due to economies of scale) your cheapest price plan would have higher margins than your larger price plans.
2) The actual cost of support issues - I've found (running xp-dev.com, which mind you, should really not have that many "dummies") that while the cheapest customers do submit more support requests, these requests tend to take much quicker in resolving, than say the larger customers.
So, I think its not as easy as saying "Cheap customers cost more". I think its better to say "cheap customers request more support"
Just a thought ...