You're probably blaming the wrong people
Not supporting Internet Exploder is a dumb decision from almost every aspect but I doubt it's because of the "Geek" coefficient of the company. More likely is that the developers have told their manager that implementing the system for all major browsers isn't a linear curve in terms of cost and development time. Then the departmental manager or MD (probably an accountant) has decided that it's too expensive to do all of them so instructs the coders to implement one or two and make it the client's problem.
As to the help desk phenomenon, nobody seems to have ever gotten this right. I know how I'd do it but, once again am forestalled by the financial director because of the costs.
Penny-wise, pound-foolish is the order of the day in contemporary IT.
