If there's the slightest indication that something could be a penalty against United, the ref always gives it.
If there's any room at all to question a penalty decision for United, the ref never gives it.
Always, always, always treated as harshly as the rules allow. That's a product of media whose revenue is measured in volume of clicks, so they print whatever gets the most clicks, and that means anything given to United is scrutinized and called into question while anything that goes against United is just handwaved away or even deemed correct when it clearly wasn't. The anti-United angle is what gets the most clicks, so that's what the media will go with. Refs don't want their decisions to be called into question, so they subconsciously choose whatever decision doesn't lead to bad press at their expense. It has had a very obvious impact on the club since SAF retired. It has basically been the ABU revenge tour.