Why would Ultimate Shocker do what he does?
There's a lot of really cliched things I could say like sick family member/loved one, is a victim of something larger, or so forth and so on.
But why don't people with great shooting skills become cops or soldiers?
Really, criminals are criminals because they've decided to become criminals. The Shocker tech is an unwieldy vibration device that travels through the air and still carries some sort of energy to tear and break down bones and steel and concrete.
That doesn't scream a lot of marketing options but there are a few:
1- Nonlethal weapons for Police and Military forces.
2- Sonic Mining Drills.
Shocker didn't try that, maybe it never even crossed his mind. Maybe he was an idiot who never was able to hold on to a buck and got the great idea that all criminals are idiots and he could rob a bank. He watched Mythbusters and thought a sonic device would be a good choice in busting vaults.
Maybe, it was designed for that and that alone. Never considering anything else, like bringing a weapon which looked like a weapon so he isn't laughed at when he shows up at the bank with a Ghostbusters looking pack strapped unto his back.
I agree, Overlord, that some villains need to ask why they never sold their inventions. But the Shocker's not one of them...he can't even name himself right...although the Vibrator isn't the scariest name in comicdom...sooo....
Asking the Shocker why he commits crime instead of selling patents or realizing his dreams in more productive ways is like asking any other criminal why they never got their Master's degree. They're criminals.
The idea of ripping off a major city bank and getting away and thinking all of their problems would be fixed forever. They're the same people who also thought in school, 'If only everyone else died and the school was on fire...she'd be mine.' Except they're still thinking like that. With the proper tech...I could go all Ocean's Eleven on that bank....
Cops and soldiers don't make as much as someone who has marketable tech to sell.
I don't see how having your design ripped off and then becoming a criminal is a cliche, its just more logical. How is what you describe not a cliche, a a lot of 616 villains (Beetle, Trapster, Stilt-Man,etc) that is a cliche and pretty lame one. It works okay if you are joke villain and not suppose to be taken seriously, but it doesn't work with a serious character. So, why give a joke character a spot light issue. Frankly this joke is played out, Shocker should either become more a serious or become a bigger joke, more goofy and over the top, devising insanely stupid schemes that would never work in a million years.
In terms of marketability, if the guy who made post-it can make a mint selling his invention, Herman should be able to do so as. A sonic drill would be a boon to the construction industry. That's already very marketable. if i invented something like that, I would patent it right away.
Really, could you imagine in real life, someone who invents something that has some market use and using it for crime instead of getting rich by marketing it, that never happens in real life.
Plus the idiot excuse works way better with Sandman and Electro then it does with shocker, seriously you have to be pretty smart to invent something new, those guy just got lucky, their powers weren't created by their own skills so them being idiots makes sense. Plus it be boring if 2/3s of USM villains are just stupid, greedy thugs, it makes them really boring and interchanable.
Another thing he could do is sell his tech on the Black market witch should give him a couple of millions aswell.
Granted, Some criminals in real life have lame reasons for being criminals in the first place....of course they don't build tech.
It could be that the do it because they like it or for the thrill of it.
Most people who are criminals in real life are poor and uneducated, they don't have the skills to invent anything. Also I doubt Shocker gets a thrill out of getting his butt kicked all the time.