"I personally think trekking poles are a waste of money."
And I will defend to the death your right to hold this opinion!
Welllllllllllll, maybe not to the death.......
Anyway, the poles are a godsend for me. They help me up steep hills, have prevented me from falling, save my knees a bit on steep descents, hold up my mid really well (while saving me from having to look for just the right height stick after a very long day on the trail when I just want to get my shelter set up), and weigh next to nothing! (I've got the Lightreks). I often carry them instead of 'planting' them when on level ground, but even then I'm swinging them in cadence and (I like to believe) creating a bit of momentum even then!