Neither does a gene. Looking back with hindsight we can see that certain patterns within the meme or the compatibility or otherwise of that meme to the surrounding culture has an impact on the survival of the meme. A meme is just an idea, it has no goals or intentions. A gene is just a chemical, it has no plan to take over the world. That which has what it takes to be replicated will be replicated.
Memes are like viruses of the mind.
As they change from host to host they change their physical make-up without losing their defining pattern. Just like a biological virus. The virus particles still in my wife neither know nor care that copies of them are now in my body, and being spread to more potential hosts. Likewise there is no payoff to an idea that gets spread, the idea has no real physical existence. A wave has no real existence, it is not any one group of molecules, it is a gross pattern of behaviour of a fluid, but it is a pattern of behaviour that can please the eye, thrill the surf-rider or flood a city.