the reason: security. if you're applying for a tech job, they want to make sure you don't owe a lot of money or have a history of owing a lot of money or have a history of owing a lot and then quickly paying it off....
if you fit the profile, you're a bad risk because you may be more likely to rip off the company using you're hax0r sk1llz so you can pay off your debts or finance your desire for champagne on a (hee) Genny Screamer budget.
See, all the hoohah about hax0rs is just like all the hoohah about shoplifting. Companies lose more to insider-based crime than ev1l hax0rz or shoplifters. But, they don't want to deal with that directly, so they *pretend* that they're worried about outsider crime to get the monies to deal with insider crime. Not to mention scare the willies out of the insiders who might be thinking about ripping them off.
i just spent a year and a half doing on an IT security--Physical security integration project for a BigA$$ Bank of 'Murika. It was rilly rilly funny to see the two cultures collide. IT security people haven't really thought of themselves as Private Sizzlean -- until 9/11, Enron, HIPAA, and Sarbanes-Oxley have forced the two departments to integrate.
As my wise bud Joe(Budge No Onan) said to me long ago when I got into this business, "It's all about control, girlfriend; it's all about control"
Kelley