Wow, there's places that actually do that?
Next they'll be mandating what you eat and when you can hit the john.
I'm not sure if by "extremely friendly", hello125 is refering to hanging out and watching the game on weekends or becoming involved in a relationship. He/she didn't really flesh out the details too much.
As for workplace romances, yes I agree that they could become detrimental, if the company/dept. is small and the relationship gets ugly. However I'm of the opinion that family/lovelife cannot be determined by your employer, your employer pays you to 'engineer', your contract of employment does not cover your personal life. And while your employer may see a workplace relationship as being detrimental, it is up to you, the employee, to be professional and to not allow the consequences of a bad relationship to ruin your working relationship.
Basically I'm saying that if YOU want to be "extremely friendly" with the person in question, don't let those tools in HR stop you, however if he/she cheats on you with another woman/man, you'd better be able to ignore/turn off any anger/homicidal tendencies you may have towards the person, come work time.