What are some examples of things that people like to crush underfoot?

People who are trying to make a positive difference in this world.  Those who can't see it should just mind their own business. 

Air mattress pumps. It is an awfully stupid way to move a large amount of air, but the only other option is the electric pump powered by the auto battery, which is also a pretty stupid thing to do unless you brought a gas powered battery charger along. So why not a gas powered inflater for your air mattress?

Spiders come to mind.

Bugs, especially crunchy ones.

Bubble wrap

Autumn leaves

"The humble dirt clod."  We all kicked a few around when we were kids.

Bugs

I like the sensation of dried leaves, pine needles, and snow under my boots. Have you ever walked in a forest, where there's a huge cushion of pine needles, so many that it's like walking on clouds and you can't even hear your own steps? How about the texture and crunch of snow? The airy crunch from a dried leaf? Weird, but these things are quite enjoyable to me.