Sometimes they do by adding some finishing touches to style up their ships, for example vessels like MARIETJE ANDREA, DEO VOLENTE, Hartman M2 Runner series.

Architect and naval enginners isn't worried with the appearence of the ships.

Maybe we can have few graffiti artist set loose to decorate the scrubbers? Banksy anybody?

Yes, Denis, but they didn't have industrial-size retrofits imposed on them. Perhaps we should have nominations for the most aesthetic scrubber retrofit on a bulker or tanker. I've opened the challenge here:
http://forum.shipspotting.com/index.php/topic,16989.msg90770.html
or https://tinyurl.com/y3vndjpu

Is that guy on the lower gantry taking a selfie or a snapshot of his mate?

Aesthetics were kept in designers' minds before the 70s.

Hello Vlad !
Unfortunately this is the future of all merchant ships "aesthetic".
Thanks for the comments !
All goods !

Once you completely disregard aesthetics, technical solutions (like scrubber re-fit) become much easier... :)
Thanks for sharing!

Cheers

Vlad