The DTV market and the theatrical release market are two different things. What does well in dtv doesn't necessarily mean it will do well theatrically. Studios want names to pull people into the theatres, and, unfortunately, Steven is no longer one of those names (from the studios' point of view, I hasten to point out). Their highest audience target market as a theatrical draw at the moment is the 13-25 year olds, that being in the 65% range. There's no way that Steven would appeal to that age group short of putting him in a movie made from a video game, and that's hardly likely to happen.
Into the Sun was supposed to be a theatrical release. Once Sony picked it up from the now defunct Franchise Pictures and the distributors had a look at it, they realised very quickly that would tank theatrically, so they sent it direct to video. They knew they had a better chance of making a profit from it as a dtv, because they would not have to spend $17 million on promoting it, and end up losing money on it. (Promotion budgets are typically about 50% of an average film's shooting budget. Why so high, I do not know, but those are generally the industry numbers.)
Success in dtv does not mean success in wide release theatrically. Besides, fewer people are going to the movies these days, preferring to wait until the dvd comes out; so why waste money promoting a theatrical release on someone who is not a guaranteed draw at the box office? Much better to let him generate the money from dtv, and save the huge sums needed to promote a theatrical release for someone who the movie-going public prefer to see.