You don't have to toss the towels anywhere but back into the washing machine. Wash them again then dry without any softener. Never use softener on any fabric you want to use to dry things, including your bath towels. The microfiber towels are best used if you completely wet them, wring them out and then use them to dry.
To clean bugs off your windows or the front of your vehicle, dampen the dryer sheets with water and wipe them off. They will smear and make a mess but it's easier to then wash them off as you would normally wash your vehicle. I've found the microfiber towels work very well to provide streak free windows providing the towels are clean when you start. Newspaper works well also...Dennis