About why Bill Watterson was so adamant against merchandising...well, let's see if I can get it all together and say what I know.
To start at the beginning, Watterson actually wasn't completely "dead-set against"
merchandising. However, as Watterson said, anything he considered has violated, he felt, the spirit of the comic. Watterson was a newspaper cartoonist not to become rich or famous (In fact, Watterson was very persistent in avoiding both), but simply because he loved to cartoon. He took his position as author and illustrator very personally, and, as Watterson put it, "Had worked to long to get to get this job, and worked too hard once I got it, to let other people run away with my creation once it became successful. If I could not control what my own work was about and stood for, then cartooning meant very little to me."
Watterson had a strong connection with the Calvin & Hobbes
world and its inhabitants. It carried the message that he wanted to convey to all his readers, and it held a special spirit that Watterson did not want to see mixed and mucked-up by petty toys and cheap trinkets for the sole purpose of raking in bags of cash.
Watterson actually turned down his first chance to be syndicated because of this. Before being accepted by Universal Press Syndicate, Watterson's work was noticed by United Feature Syndicate. United Feature Syndicate's interest inspired what became our beloved Calvin & Hobbes
, but before they would accept it, United Feature Syndicate insisted that Watterson work in a propeller-headed robot into the strip. United Feature Syndicate, you see, had just acquired rights to this character and was preparing for a major licensing program. The best way to promote it would be to give the robot his own comic strip. Watterson, though, was offended by both the thought of writing and drawing a character that wasn't his own, and writing a strip just to sell merchandise. Watterson decided to decline.
Also, as I said at the beginning, Watterson was just a cartoonist. He loved writing and drawing Calvin & Hobbes
, and wasn't interested in all the fame and money. Famous people always have to make appearances and deal with mobs of fans. Rich people always have to manage money and stocks and stuff like that. Watterson, plain and simple, did not want that. He was happy with what he had. Merchandise could also end up posing some limitations on what Watterson could do with his strip.
I myself deeply respect Watterson for sticking up and standing by his view. It all was a bit weird, but I think he did the right thing. Of course, I personally am the kind of person who would rather make fan toys than buy mass-produced, over-priced spin-off products. It wasn't a big loss for me.
...not for sale, of course. Okay, that's my two cent's worth. Most of this comes from Bill Watterson's introduction for The Complete Calvin & Hobbes
. I really
hope it helps a bit.