We use ASO and DV on our DB Site, I think ppl doesn't use them too much since their price is set too high, and many features used by these products require a very specific security requirement (f. ex. comply with SOX or PCI) and many customers don't have that need.
Well, I believe that you are not at the right customers then :-)
I do regularly work for customers who use some - if not all - of the Oracle Security products.
Often customers are not even aware that they use Oracle products. For example at the last company I worked (very large multi-national consulting company) all security and IDM stuff was powered by Oracle. But as the look and feel was integrated into their corporate style only a few people knew it was an Oracle product that did SSO, user management and the like.