She is not using her eyes while bathing and sleeping!
sleeping she closes her eyelids but bathing she does have her eyes open
if you mean just not having the sharingan not activated then what is the point of her wearing it right now, especially since she had them before she unlocked her sharingan
if you stated that the eyes are preventing her from unlocking a intense sharingan eye MS/EMS/new thing then she wouldn't be blind without her glasses since she wouldn't be wearing them
if you stated that Karin sealed her eyes first then gave her glasses due to that seal then it would've been more rational then the glasses being the seal.