Well, how bad do you want the file? They're counting on you wanting it so badly you'll pay. I've seen a lot of file hosting sites going this way - giving uploaders a bigger payday if they'll limit downloads to paid accounts only. It's getting very difficult to be a leecher these days.
Fortunately most content is not unique, and the same files get uploaded over and over. Look at filestube.com or rapidlibary.com for what you want.
Or just wait - someone will repost the file. I waited a year or more for an obscure math book to get reposted when all the links were dead.