Maybe it just boils down to the right to property and having your own stuff just the (legal) way you want it.
It's all great until your stuff gets destroyed because someone thinks it's better a different way. And when the graffiti is truly spectacular you can find some consolation in the result, maybe truly appreciate it. But that's not the case 99.99% of the time. Most graffiti is just trash, some rando spraying their name somewhere. Takes 10 seconds and 0 talent. It causes extra expense for people or the city to clean up, or it stays there as an eye sore for everyone.
It's all great until your stuff gets destroyed because someone thinks it's better a different way. And when the graffiti is truly spectacular you can find some consolation in the result, maybe truly appreciate it. But that's not the case 99.99% of the time. Most graffiti is just trash, some rando spraying their name somewhere. Takes 10 seconds and 0 talent. It causes extra expense for people or the city to clean up, or it stays there as an eye sore for everyone.