I would assume the first part is to get customers. From my own experience when I was just starting out, it wasn't the encryption model that attracted me to an application but the number of encryption types it supported.
It's stupid from a user that understands how these models work but from a casual point of view, can you imagine a user hearing how all these models are good enough that no one can even crack AES-256 for a long long time? Then factor in that most users aren't that anal in keeping their files private (the whole obscurity matters more in privacy thing) and then multiple models just start to look more attractive from a casual buyer perspective which seems to be the target market of Androsa.
