Women like that can be bloody awful but cashiers and waitresses don't get walked to their car or go home in pairs or call the police because of Karens. It's always terrifying men who stalk them on social media, wait around outside their workplace, stare at their name badge and use their name inappropriately (I disapprove of name badges!) or just shout at, threaten or rob. No memes for them though.
You know what sticks with you after a long shift working with the public? Not some annoying entitled woman. Being terrified sticks with you. Being hurt sticks with you. Being sexually harassed sticks with you. No memes for that though.
Whilst I agree that stalking women is undoubtedly worse, I don't think we can so readily dismiss female bullying and intimidation, especially when the power dynamic portrayed here is typically that of a white, privileged, middle class woman bullying either a younger woman or somebody of a lower socio-economic status in a service role - perhaps a BAME individual. Dismissing this is a bit like dismissing sexual assault because it's not as bad as murder or rape.
They're quite different scenarios in my mind. Being stared at on the way to the car is horrible, but on the flipside there is no question as to who is the perpetrator there. However, when 'Karen' complains to the manager the dynamic is different. The customer is always right, and we have a confident woman going up against a victim who is likely younger and may feel intimidated or fear for her job, hence very possibly being reticent to defend herself and maybe accepting the blame - what has Karen to lose from this apart from some misplaced pride?
I can imagine the manager siding with Karen in many instances. We've all seen it before. Waitresses are easily replaced but an angry customer can seriously damage a business's reputation. People like Karen know how to complain and they do it often. It's unreasonable to use the name 'Karen', but we all know somebody like her. Once she starts making a scene the manager will want to placate her, and he certainly won't want the fallout of a slew of bad reviews on Trustpilot/JustEat/Google reviews etc. If it doesn't affect the business's reputation then the manager still likely has to explain the situation to the owners.
Sadly, after an encounter with Karen, the waitress may not be walked to her car. She'll walk to it on her own after having been fired and she won't be coming back. Her terror won't be of somebody using her name inappropriately, it'll be of how to keep a roof over her head and feed her children.
What's concerning is that the prevalence of this stereotype would suggest that it's an extremely common occurrence.