SINGING THE WALLPAPER BLUES FOR MY SUPPER

I went over to my my brother's wonderful girlfriend's house for supper tonight. She didn't make me sing for it, exactly, but my arms sure are sore. The wallpaper border in her bathroom doesn't match the look she's going for in there, so she asked me to help her strip it. I scored it, and coated it in this wallpaper remover stuff. And being a person who follows directions, I waited a half hour. Then I started to scrape it, but LO AND BEHOLD the previous tenant (it's a rental) used paste that was not water soluble. (NOOOOOO! Why God? WHY?) So I called it a day,and we decided to use something stronger later. Instead, we sat down and I showed her how to use eBay. Why on Earth would somebody apply non-strippable wallpaper in a rental?