Quite a few 'WTF' moments over the years and I've worked for big blue chip companies as well as the charity sector. Spoiler alert I've come across far more twats in the charity sector...
A manager taken through disciplinary for racism and allowed to keep his job "because he's got kids".
The same manager encouraging his team not to take loo / drink breaks to help with their call stats (rather than giving any coaching / support / performance management). Also telling them which days their calls were going to be listened into for quality checks, so they could do things 'properly', before reverting to getting people off the phone as quickly as possible with no real care or thought of the impact on service users (who sometimes needed quite complex in-depth advice).
Another manager (same charity!) sexually assaulting a colleague on a night out (not a works do, a social drink). She didn't feel able to report to police, but did make a complaint at work as he was senior to her. Despite a number of witnesses (including me - he basically put his hand right up her skirt and grabbed her in public) he also kept his job, though he was warned about future conduct.
Same charity - a staff member ended a call with a client who became racially abusive to them (all calls were recorded). Another staff member was told to call the client back and continue with advice and apologise that the previous call was terminated. Absolutely no support for the staff member who had been abused, which left many frontline staff feeling unsafe / unsupported.
When I was much younger I worked in a call centre for a mobile phone company. It was great money at the time and I found it easy tbh. I was never late or off sick and had a good work ethic. I'd been there 2 years when I took 3 days of sick leave with the flu (proper flu, couldn't get out of bed, very weak etc). We were lucky enough to get occupational sick pay, all good.
On my return my manager proceeded to tell me that as I had been off over a weekend day, I would need a sick note. Errrr no I don't I was off for less than 7 days? Manager reluctantly acknowledged this but then said as I didn't have a note I would need to take annual leave instead of sick leave. This actually didn't bother me as I had plenty of days left and thought it would keep my absence record clear. Oh no, the official policy was that I would need to use my annual leave, but it would still be counted as sickness absence. WTAF?? This was confirmed by HR and I ended up going to Citizens Advice who confirmed that this was bullshit (I'm paraphrasing). Also they counted Monday and Friday as 'weekend days' so you could basically be ill 3 days a week.
So I arranged a meeting with my boss / HR to clarify the legality of what I had been told and the cheeky fuckers expressed 'disappointment that I'd felt the need to take advice'. Absolute pisstakers. BUT...an email went out the the whole contact centre the following week confirming that if we should choose to book annual leave to cover sick days, then they could not be counted as sick days.
I've definitely heard of far far worse things, but these are probably the worst I've ad some direct involvement in / awareness of.