I've had similar experiences at some hackathon events. The local Startup Weekend event a few years ago was similar, but in some ways that is more predictably skewed to who can give the best pitch, so that one didn't rub me quite so bad.
Along the same lines, there were a few local meetups where people were going to plan some ideas for innovative uses for public data sets, and what kind of data we should try and get released from the city & county. The whole thing ended up getting de-railed by non-tech "thought leader in a turtleneck" consultant types giving their personal pitches to market their brand, and nothing solid came out of that. Those who were interested in building something formed a separate group and went their own way.
At the risk of sounding like a delicate snowflake, I would really enjoy more "tech events for people who really want to get their hands dirty".