Sure, there are plenty of techs you don't need. If you have no camp resources, you only really need hunting if you need archers for some reason. That being said, due to prerequisites for techs you DO need, often you'll have to pick up the useless techs along the way. The biggest reason for skipping certain techs intentionally, though, is for bulbing strategies. I know skipping fishing leads to a different bulbing path, for instance.