Here are some scenarios.
1. You work at Shipping Giant processing packages in a distribution center. Since you work in the middle of the night, you cook up an easy scam with your friends whereby you identify obviously valuable packages (for example, a crate of Playstation 4s) and change the addresses to redirect them to your friends. You quickly sell the pilfered goods on eBay, Craigslist, pawn shops, etc and split the profits. Eventually one too many packages turn up missing. Company security watches you closely and catches you in the act.
2. You work at a busy cash-only bar. With literally thousands of dollars in small bills flying around every night, it's very easy to pocket the occasional $5 bill as "bonus money." You also sell drinks out of your own bottles of liquor (come on, you remember the scene in Road House) and give away freebies to friends. The boss notices on a slow night and calls you into the back room.
3. You're a cashier at Retail Giant. You arrange with an accomplice to scan a barcode for a cheap item over the barcode on a much more expensive item. Too many electronics end up missing and eventually the security cameras catch you red handed. The manager on duty discreetly takes you off the floor and into the office.
All three scenarios are a variation of the same theme: you, the employee, are stealing from the employer. In addition to termination, what are the odds that any of these scenarios would not end with you in handcuffs facing eventual criminal charges and jail time? I'm going to estimate them at zero, plus or minus zero percent.
Simple enough. Now here are three more scenarios:
4. You work 55 hours per week at Shipping Giant but never receive the overtime pay required by law. After some complaints and threats, the company creates the legal fiction that you do not actually work for Shipping Giant but instead a subcontractor or as an "independent contractor." Thereby they exempt themselves from legal requirements to pay you 150% and effectively steal 7.5 full hours of pay from you for every 55 hour week.
5. The owner of Busy Cash-Only Bar illegally confiscates and takes a heavy cut off of your tips at the end of the night. Often what you receive in tips is below the "estimated" amount of tip income on which you must pay taxes.
6. Retail Giant regularly has you work another hour or two after clocking out. When you do submit a time card with the phantom hours included, your paycheck is still for 40 hours on the dot. You find that your time card has been altered by the manager to make the would-be overtime hours disappear.
All three scenarios are again a variation of the same theme: the employer is stealing from the employee. Odds on handcuffs, police cruisers, and criminal charges being involved? Again I'll go with zero. The absolute best the employee can hope for is to file a lawsuit to receive what he or she is already legally owed (minus the 30-50% cut the lawyers will be paid for their services) and get it after months or years of litigation.
These six scenarios, regardless of what semantic games we play, are essentially the same. Legally and morally, they all amount to theft. The employee is taking things to which he or she is not legally entitled or the employer is taking the employee's labor without paying the compensation required by law. In one set of scenarios both justice and punishment would be swift and severe; in the other, justice is an uphill battle and punishment is nonexistent.
Employment is a legal arrangement. You provide something of value to the employer in return for compensation at an agreed upon rate. As simple as that seems, we appear to have forgotten that collectively.