I am only making my mule for personal and guild use. I got tired of shopping for what I needed. I just purchased 10k ingots at 160k. Also the only reason I got a good price for the ingots is because I got them from a guy in my guild. Yeah, another big factor is time.
Smiths consume ingots far more quickly than they can be produced.
I usually balance my time with an hour of smithing with an hour of mining, but mostly the hour of smithing is reduced to a half hour. But basically, I agree with the basic premise that there are too many smiths and not enough miners. Another item not to ignore are house add-on makers, who consume a good amount of ingots as well. The solution would normally be to mine one's butt off and make a killing. Thus, the only solution left for smiths are to suck it up, lower your stock, raise your prices and mine your own ingots.