There is lots of money in making HL7 systems talk to each other though. Getting dialects to actually communicate is quite easy to charge a lot for. However finding someone who will do it is considerably harder.
Yes. HL7 is sort of thing you can dip into a bit, and think, "Wow... whole rooms of contractors are racking up big bills dealing with this." For me, HL7 is the analog to chemistry's wonderful "Things I Won't Work With" blog.