It's important to have standards in the workplace. Imagine if you went into Starbucks and the baristas were sitting on top of the counter, absently necking whipped cream right out of the canister. You'd probably just turn around and head straight for the competition.
In WWE, standards are slightly more arbitrary. Wrestlers only interact with "customers" (i.e. the fans) for a fraction of their working lives, with the remaining part spent in the company of their co-workers. As such, the onus is not so much on acting professional as it is on not acting in a way that will annoy one of the locker room leaders.
Unfortunately, not all of them have been successful in negotiating that line. The internet is awash with stories of WWE employees upsetting their backstage superiors, and more often than not they are met with the kind of punishments that probably wouldn't fly in any company with an effective HR department.
Sometimes, though harsh, they appear more or less fair. Baron Corbin being robbed of his push for being a possible jerk backstage, for example - you can get behind that. It's not like he lost his job or anything; he was just given a sharp demotion from the main event, to where he could yet return some time in the future.
And then there are those that seem ridiculously excessive....