One Bill = One Idea

One thing I find frustrating is that congress can pass a bill with "hidden" mini laws.

For example, congress recently passed a bill to reform credit card companies and it also included a provision allowing people to carry handguns into national parks. What? How do those two ideas relate?

Those items should have been two separate bills. I know politics is about compromise; but, I want congress debating the details of credit card reform and not slipping in a gun law so that they can get a few extra votes. This seems disingenuous.

Each bill should focus on one idea/concept/law. This only seems fair.