Quite simply, if anyone started giving me that kind of grief I'd be straight over their head to their manager/director/VP. IT/admin work is hard enough without people giving you this kind of stick.
Thankfully I work for a company where the managers are flexible toward us IT types - but I've had the odd programmer get all uppity about me logging onto his machine only for them to be told "remember, it's the company's machine. And Peter's the company." :)