A hole can be fixed. An app that saves data, plain-text or not, is just that. The real issue is WHERE these apps are running: on mobile devices which, if not properly secured, serve as an easy target when stolen or lost. Is a non-secured iPhone filled with holes since all of your contacts, e-mail, etc. is stored in plain-text?
And even when they do get a new PC, they often times switch back!! My previous place of employement would order brand new IBM PCs with Windows2000 and overwrite the hd with an image of 98!! Why?? Because there is so much software still out there that does not work well with NT based OSes (2000, 2003, XP).