[cooooooffffeeee]

Yes and no, visitor badges often don't use RFID. You can get most places if you have a visitor badge and know someone's name (which are all available on LinkedIn). If you get stopped with a badge you can just say "Oh I'm here with so-and-so in X Department" and usually no one follows through beyond that. Saying you're there for an interview will often drop someone's guard too.

Employee badges often do have RFID, but some places just have you use a sign-in sheet if you're an employee and "forgot" yours (i.e., you don't have one), and sometimes security guards will just let you through if your badge is being "temperamental" (i.e., not working because it's fake).

Most corporate security is security theater (or only marginally useful after a crime) and rules are easily skirt-able because companies don't want to restrict employee access under zero-tolerance policies (which are difficult and time-consuming to enforce).

The company I mentioned previously that will just hand-waive you through a gate with no barriers actually goes as far to fingerprint all their employees and contractors. They also won't hire anyone with even a misdemeanor in their criminal record.

Also note that all of this stuff is markedly easier if you're a woman (less likely to be stereotyped as a criminal) and/or if you wear a suit (depending on the office, a suit can often mean "don't confront me because I'm above your pay grade").