Q: If it's not vegan to ride horses, is it vegan to watch shows such as Game of Thrones? Is it vegan to watch tv shows that use animal actors? Being vegan is impossible because no matter what you do, you are harming animals.
A: Vegans try to reduce animal suffering as much as practicable. Just because it's impossible to be perfect it doesn't mean there cannot be progress. Just because you cannot save 100% of your income it doesn't mean you should not save at all. Just because it's impossible to achieve perfect sterility it doesn't mean you should perform surgery in the sewers. Just because I eat plants or cause harm to living beings by watching Game of Throne, it doesn't mean I should rape a little girl. It's pretty obvious, but we humans tend to grab into any rationalization to justify some habit or prejudice we already hold.