Stopping and going zombie hunting is the best! You can maximize your kills and saves, increase your stats and it helps with knowing how to shoot better.
Skipping costs are ridiculous! No longer getting the opportunity cash in in on the mission should be punishment enough. I mean costing double sometimes is unreasonable!
 "Road of the Dead 2")
 "Soul Tyrant (Beta)")
 "Sheep Happens")
 "Zombo Buster")
 "Awesome Pirates")
 "The Peacekeeper")
 "Giants and Dwarves TD")
 "Miscrits"){kind=icon}
Thanks for the comments!