Meanwhile our IT technicians are dicks and everything is blocked. They even made us sign a contract that is almost certainly illegal to enforce. Pretty much says that you can only use the computers for work and you can't do so much as plug in a USB drive without permission.
Spoilers: It's because they're not actually very good at their jobs so they're scared of anything they don't already know well[/spoiler]
Well, I'm an IT tech and while I'm not that strict I can relate. Most likely is not that they are bad at their jobs. Most of the time when you see a thing like that is because there's some precedent. USB thumbs can be pretty dangerous either unintentionally or intentionally.
You might know what you are doing and not trying to mess up the network, but what about everyone else on the office? Your coworkers might not be as well versed on computing as you, and might end up bringing a nasty virus from home, or the other way around, they might know exactly what they are doing when trying to sabotage something. I have experienced both cases first hand.
Most of the time there's one guy that ruins everything for everyone else by trying to be too smart, get caught and hence a reaction from IT would be to create a policy over that. (Happened here too). Most of the time IT becomes as unpopular as human resources because you are forced to cut the wings of people.
Also let me add that computers at work should be used only for that. Work and nothing else. While a little slack can be cut most often than not people eventually abuse from it and you are forced to put tighter limits. For example in my contract it says that I have to provide support, blah blah blah and make sure that all the computing assets of the company are used only for work. It's pretty standard and not illegal anywhere I know to have a contract that include something along those lines for users. I'm fine if people bring their smartphones and use them to whatever they want, after all it's their time. The assets under IT care are what must be "protected".
EDIT: And know I realize I replayed to a message over a month old in a thread that already changed the subject and forgot about it. May Armork have mercy unpon me.