What is your IT Department's Purchasing Power?

I read this article today http://www.cio.com/article/676689/Moving_to_Cloud_to_Gain_Agility_5_Lessons, and it got me thinking (I didn't find it on my own... Joe The IT Guy tweeted it.... and I must admit, that I read a LOT of the articles that he tweets).  How many companies let their IT department manage their own budgets?  In today's world, instant gratification is almost expected.  How does your company pay for IT purchases?  Do you still use purchase orders?  Do you have a line of credit that you purchase everything with?

Why don't businesses give their IT departments corporate credit cards and let them manage their own budgets?  That's how I operate here - I put everything on our American Express, and then if we need to finance something, that's all taken care of on the back end.  It just makes sense, at least to me.  When I need to buy something, it's generally  not because we "want" it, but because we "need" it.  How many hoops do you think we should jump through to replace that switch that just fried itself?

Are the people in the Executive Office or Finance Department afraid that we'll spend a year's budget on the coolest gadget because we just "had to have it?"  Of course not!  Those of us that are gadget obsessed will gladly drop our own dollars on the latest and greatest gadgets, but when it comes to corporate spending we're much more cost conscious - or at least I am.

I think that most of us understand that in IT we are here to create solutions and provide systems that help the company as a whole.  Amazon EC2 can provide an organization with a lot, but your account must be paid for with a credit card.  In my personal life, I can't tell you the last time I wrote a physical check.  I either use a card or send a check via online bill pay.  Why are businesses so enamored with checks?  Would it not be easier to write as few checks as possible and give employees the power that they need to do their jobs well?