Do you think Puns are a low form of humour

I enjoy them. Its at the point where I throw puns into normal conversation, hoping people don't get it, which makes it funnier to me.

Once I was talking to a friend and I brought up a topic with the sole intent of punning her later on. She ended up revealing some pretty personal stuff that she obviously hadn't told many people and when I finally pun'd she got it and was like; "The last hour of conversation is meaningless."

Does that make it a low form of humour?
Should I not have punned?

For Example:
A thief in Paris planned to steal some paintings from the Louvre. After careful planning, he got past security, stole the paintings and made it safely to his van.
However, he was captured only two blocks away when his van ran out of gas.When asked how he could mastermind such a crime and then make such an obvious error, he replied, "Monsieur, that is the reason I stole the paintings. I had no Monet to buy Degas to make the Van Gogh."

(You thought I didn't have De Gaulle to post this, but I figured I have nothing Toulouse.)