Yes, most medium-or-smaller sized companies, including ones in fields that should take security seriously like insurance and lending, will have tons of stuff like this. It shouldn't surprise anyone at this point.
Even large companies depending on how you want to classify one as "large". Back when Palm announced their new phone, the Palm Pre, I was given early developer access on their developer portal. I reported to them multiple security vulnerabilities including one that allowed anyone to change a simple integer in the URL and instantly see everyone's SSN / TIN, payment information, etc. It took them 3 months to fully resolve, too (their first fix was simply changing a GET call to a POST, sigh). They never even disclosed it to anyone despite my pleas (I should have but was still sorta green back then and didn't think it through).
