Assuredly options exist at the moment, but if every new reader that now comes on the market does not accept the pre-existing mobi/epub/etc formats without us having to jump through numerous hoops, then those options reduce to what Amazon and Apple et al are prepared to allow us to use.
Until Amazon introduced the kindle, readers were independent of books - increasingly they are becoming linked. At least the iPad has a kindle app (has the reverse appeared ?).
Am I going to have to investigate a kindle or iPad app for my Gen3 or Pocketbook in (say) 5 years time ?
Is this the way we, as customers, want the market to develop.
Not that any of us have a cat in hells chance of altering....