Marriage material?

So my bf and I have been together a little over 3 years. We have gotten to the point of discussing marriage. He is not really religious at all, and doesn't necessarily have much of an opinion about marriage. He said he always thought of it more as a legal action. He says that the only reason he has considered marriage is because he knows what it means to me. Should I be concerned about this, or glad that he is willing to take that step for me? 
-he flat out said he was doing it just for me, which is what made me wonder.