Now I'm in IT and this is one of my biggest peeves. It's is illegal, in violation of copyright and licensing laws. The Software Publishing Association can slap you with a $100,000 fine for each violation, REGARDLESS of the value of the software.
I have idiot users coming in here day and and day out, installing crap on their work PCs, something they brought from home and just assume it's OK to install here as well, since they paid for it. They apparently didn't read the fine print that stated "this is a single seat license and may only be installed on one PC at a time. Do not make illegal copies of this disk, or allow others to access it."
I couldn't care less about what people do at home, but when they bring it to the
business, it's my problem. A disgruntled employee contacts the SPA, we get audited and they find unlicensed software....that's a very hefty fine.
Sorry....I just had to uninstall a bunch of junk from one of these users.....