It's a rather general problem. It has ads, requires scripting (to view text!), breaks formatting, doesn't have sensible syntax highlighting available, etc. Imho, it's probably the worst paste client anyone could use for anything. http://ix.io and http://sprunge.us are significantly better alternatives.

But, if one is dead-set on using pastebin.com, the least they could do is post the raw link so users can escape some of the horrible.