Random  examples of non-funny viola jokes:
“Why should everyone have a viola around the house? Because you might run out of firewood.”
“How do you get the viola section to play in tune? Have them play a measure with a whole rest in it.”
Why is it that people make so many jokes about the viola? One website I have seen has almost three times as many viola jokes as it does violin jokes. There are far more than three times as many violinists as violists. Perhaps viola jokes are like fishing in koi ponds—chosen because people are cowards and like the easy way out. Let us suggest how.
For one, violists are far more rare than violinists. If you make a viola or violin joke, it will probably only be funny to those who are familiar with string instruments. Yet, as violinists far outnumber violists, and most people are cowardly when it comes to humor, it would make sense on the numerical level that people would make more fun of the minority than of the majority. Jokes do not tell us about the people who are being joke about, but rather about the people making the jokes. They tell us the sort of ridicule and hostility others have in their heart, and their desire to amuse themselves by making fun of others who are numerically smaller and thus (presumably) less powerful than them. The commonality of viola jokes ought to tell us that a lot of would-be orchestra humorists are moral cowards.
More examples of non-funny viola jokes :
“Why do so many people take an instant dislike to viola players? Why wait, it saves so much time.”
“Why are violists ears so sought after for transplants? They’ve never been used.”
“Why do violists get antsy when they see the Kama Sutra? They can’t handle any subject reference to “more than one position.”
“Why is a violist like a a terrorist? They both screw up bowrings.”
“What’s the difference between a violist and terrorists? A few people actually like terrorists–their mothers…”
“Why is a viola like a lawsuit? Everyone is happy when the case is closed.”
“What’s the difference between a chainsaw and a viola? A chainsaw has a better chance of blending in a string quartet.”
“What do you call someone who hangs around musicians a lot? A viola player.”
“What do you call a violist with half a brain? Gifted.”
“What do you call a violist with more than one brain cell? Pregnant.”
“What do a SCUD missile and a violist have in common? They are both offensive and inaccurate.”
“Why do violists make effective rapists? Because it’s hard to fight back when you’ve got your hand over your ears.”
“What’s the most effective form of male birth control? Tell the girl he plays the viola.”
“Why don’t violists play hide and seek? Because no one will look for them.”
“Why don’t violists take up mountain climbing? Because if they get lost no one will look for them.”
“How do you get a viola player out of a tree? Cut the rope.”
For another, a certain type of person is attracted to the viola as opposed to the violin. The viola and the violin are about the same size (the viola is a little larger, but not tremendously so, unlike the cello or string bass), and the viola is a little lower than the violin. So what would make the viola appeal more to someone? Presumably the fact that it was obscure and unusual. Violinists are a far more competitive lot of person than violists. Violists, by and large, are quirky individuals who like to find obscure niches for themselves. Violinists fight and compete to be first chair, struggle to keep up with the Jones and the Lis and all of the other people who sit with them who are likewise all competing for a few spots and for glory. Even for a first chair there is little glory to be found, so I have found violists by and large to be far less competitive and far more congenial in orchestras, when another violist can be found, that is. Far too often I have been the only one. Nonetheless, the difference between a hyper-competitive violinist and a more nonchalant violist, combined with the quirkiness of the violist in general to have such an instrument appeal, tends to create a lot of room for humor of misunderstanding.
Let us also remember that some viola jokes reflect problems with the orchestra in general, and not necessarily violists in particular. For example, one viola joke goes as follows: “How do you know a violist is knocking at the door? He never knows when to come in.” Why would this be so? If you’ve ever tried counting for 45 measures of rest while playing “In The Hall of the Mountain King” you will find that sitting around doing nothing during most of a song is fairly difficult to manage, when you are supposed to be playing the the rest of it. Even whole notes would make it easier to keep time than 45 measures of silent counting. That’s not the fault of the violist, it’s the fault of the composer.
I suppose if I were a person more given to humor and levity and who enjoyed jokes more that viola humor would not bother me. As it is, I’ve heard a lot of very bad viola jokes (“What happens when you throw a violist and a soprano off a cliff? Who cares?”) and only a few really good ones (most of them obscure and involving different fingering positions on a musical instrument). Perhaps that is because humor is like many human endeavors where it is easy to pick low-hanging fruit and not easy at all to reach for glory or excellence. Until people try harder, and show a little less cowardice at picking on easy targets, I suppose we will lack better orchestra humor.