Wikipedia:More rights does not mean better
 | This essay contains the advice or opinions of one or more Wikipedia users. Essays may represent common ideas, or ideas that many users would not support. They are not rules. Think carefully about what they say before following them. |
 | This page in a nutshell: Being an extended confirmed user doesn't make you better than others or give you the rights to be a vandal. |
Many users think that having more user rights than other users makes them better or gives them the rights to vandalise a page, but that's not the case. Once you have been granted these rights you should rather help others than act like you're better than them. you should also help fixing pages instead of vandalising them.
Why?[change source]
Because that's one of the purposes of Wikipedia, offering a safe space for everyone including readers and editors rather than being an unreliable, not safe, bad and a website which everyone avoids. Breaking this purpose makes you a bad editor that everyone hates.
I found a person abusing their rights, what do I do?[change source]
Keep assuming in Good faith and report it to any active Adminstrator or open a topic about it in the Administrators' noticeboard so that Administrators can be aware about this person and try to warn or even block them.