My sister moved house and noticed a weird smell from the kitchen sink. Plumber found a mini fatberg down the drain. The old bloke they bought the house from had been tipping everything down the plughole. For years.
How does this happen? Is it more for things like bacon grease rather than cooking oil? Because cooking oils are usually (not always, coconut oil for example) liquid to lower temperatures than water.
No, they'll just tell the landlord. You don't rent, do you?
It's the landlords responsibly to repair the sink. A place being rented full-time to different people can't be blamed on any one tenant even if this wasn't the case.
Public infrastructure can be built to handle it but it is significantly more expensive, and since a lot of public infrastructure is incredibly old you are damaging pipes and causing bills to go up for everyone in your area