Why can't Microsoft replace the Lumia 535 touch screen via service centers?

[WPCentral Question]

why Microsoft is not trying to replace the touchscreen. i am a hardcore windows fan . i am also satisfied with 535 but this touchscreen cannot cannot be used in wet conditionand also giving me lote of probles even after the new update in march. i was wondering why Microsoft is not going for a touch screen replacement as a consumer i am willing to pay the money for replacement also

 

[hotphil]

It's probably not economically viable for them to replace it that way.
I'm not sure using a phone in wet conditions is advisable. But hey.