Agreed. There are a lots of companies tackling this problem, for all sorts of niche solutions (texting students to remind them of homework, restaurants texting customers that their table is ready, etc.)
As you said, there are a ton of niche companies that handle this. Just look at the attendee list at the Bar & Nightclub show in Las Vegas. I work for a company that provides a similar service, but we have a short code and work directly with the carriers. Lots of competition and not a whole lot of margin if you don't have the volume drive cost down. Good luck to the, but free isn't going to last too long.
