See for yourself: to bring a mere 1 pound of laundry to the International Space Station costs more than $10,000. So, it costs less to throw the clothing away when it gets dirty than to waste water on washing it.
Maybe the keys are getting grimy or has dirt or something like that or getting wear on them, but the electronics underneath are perfectly good and can be reused.
Pollution means getting the environment dirty, but if you minimize something, that means to reduce it, The opposite of that word minimize is maximize, to increase something.