I'm not sure I'd go that far, but puns are certainly a clever, entertaining and stimulating form of literature. They invite us to dig around for subtle meanings, sounds, rhythms and broader implications. This is good for our brains. The fact that the result is fun adds greatly to the benefits of these word clowns.
As many people know, Archie Bunker was a master punster (thanks to his own wit and that of his writers). Here's one of his that no one (especially Edith) would argue with: "My doctor tells me I got a communications disease."
A more current form of word play that I enjoy are the #Hashtag Games on Twitter. Here are two of my favourite ones that involve punning:
Frankly, my dear, I don't give a yam.
The pen is mightier than the gourd.
#Home Improvement Movie
Look Who'd Caulking
I like puns because they make me slow down, root around in my vocabulary and try to send out a zinger that will make somebody chuckle. It doesn't always work. Sometimes puns just bring on a groan of agony at their lameness. But even a groan is more fun than nothing. To add to that, I really love it when somebody can throw one out at exactly the right moment. That's just so choice!
And since having fun with words is a big part of what I'm about...well, it goes without saying that a good pun will always get me either grinning or groaning in depreciation.