The problem is selling that better way.
If they had done things the way you say, their price point would have been higher, while everyone else who didn't do it is lower.
I've been in many budget meetings where Product X does A, and Product Y does A too. Both products let you put a check in the audit box. Product Y is 20% cheaper than Product X. Without a glaring fault in Product Y, nobody will spend the extra money for Product X.
The audit question is often worded: Is a centrally managed antivirus product installed on every PC? Are the definitions for the product kept up-to-date? Good! Pay us for verifying that(among other similarly useless questions) and here's your SAS70/SSAE16/SOC1 papers.
Customer says "are you audited? can I see your papers? Good. " -- due diligence is considered done.
The people performing the audits rarely have a clue other than knowing that there's supposed to be a check in that box.
It's all a game of CYA and security theater, with very little real security being practiced.