The full sandbox are for the paid version, there have to be differences or what incentive is there to purchase the Pro/AIS applications. The programmers have to eat too, so if you feel that sandboxing is so important them you could purchase the Pro/AIS versions.
As has been said the autosandbox isn't anything other than an analysis tool over and above normal virus signatures to be used when files that although considered suspicious aren't detected by conventional signature. The fact there appears to be a happy coincidence that in Ask Mode, it may be possible to run the app sandboxed.
But I would advise not to make such a big deal of this or who knows the developers may close that hole.