It's a mouthful, isn't it?

The reason that it's so long is that the representatives in the National Assembly wanted to make it clear that they weren't actually offering rights to everyone. At first glance the Declaration of the Rights of Man and Citizen sounds great, but those last three words are important.

The rights only apply to men, and they only apply to French citizens (which at the time were defined as property owners). Sorry French ladies and renters, you don't have rights yet.

While the U.S. Constitution and Declaration of Independence stays vague on these ideas, allowing people to assume that they meant mankind or at least all men regardless of wealth, the French didn't want to get people's hopes up. Only men who owned property could vote and participate in the French government.