Yes, for about the last 40 years, which should be long enough to eliminate the memory of a day when things didn't crossmatch, because even in my southeastern state we got those "newfangled" things called computers with little green screens and all unemployment data was centralized. But when unemployment insurance began in the 30's it was laboriously done by hand all in little local offices where the employers were contacted and data was collected by the same local people who were writing the unemployment checks, so they knew pretty much if Joe Blow was working or not.
I remember an old fraud investigator laughing about the old days, when he had to go after these old construction workers who'd drawn some of the first unemployment ever distributed and thought it was standard operating procedure to file that one last check after they'd gone back to work, because they were going to miss a week with a check before their first paycheck, and considered it their God given right. For some reason, people who would never dream of stealing, who are in church every Sunday, would think nothing of cheating the system, just this little bit and think it was okay. Sort of like cheating on income tax, or lying about how much you paid on that car you bought.
One thing you could count on, even then, was that even if you were successfully fooling the system, people were eager to rat you out. There were always the reports you got from your ex wives, your irate buddies, brother in laws, etc. Since they are required to make a certain number of random checks per week on people who are drawing unemployment, they always make those random checks on people who've been called in on. And an amazing number of them turn out to be the people who are committing the fraud.
Don't kid yourself though. This is very small time crime. People get really upset and indignant about it, but in the big picture, eliminating all unemployment fraud that ever was perpetrated wouldn't make even the tiniest dent in the vast pool of "government waste and fraud." And it is not somebody stealing your tax dollars. All the tax dollars put into the system are the ones to hire the workers who make the system work, not the pay of unemployment. The unemployment money (except in the case of federal extensions) comes from the collection of taxes from the employers of the states based on the number of people on their payrolls.
All the huge waste and fraud sins are at a much higher level, and a whole unemployment claim in any state isn't enough to sneeze at when it comes to criminal activity. That's why it comes down to most people not being prosecuted, though technically they could be. And since it does NOT come from taxpayer money, but from the employers accounts, those employers are on the spot encouraging that the system chasing down every cent so it can be restored to them, not the taxpayers. We don't get into whether they're cheating on their other taxes or not.
The thing about unemployment is that it works fairly well to self fund, and it for the most part does catch those who try to cheat it. It's not based on need, any more than Social Security retirement is, it's based on qualifying based on your work record, which we do keep up with, and it doesn't work any better to try to cheat on it than it does to try to cheat on Social Security retirement. Thank God for the federal bureaucracy, it certainly works better than any alternative I've ever seen to keep the system working at some level.