If they prevent my death, I don't care why.

Psychopaths are overrepresented in surgery/EMT work if I'm not mistaken, for better or worse.

That would be fine, but what if it is a slightly different "I don’t really care about my patients’ lives. I just like the power of having a hand in whether people live or die."? Doesn't that start to sound a little questionable?

As Dan says "The goal is to protect the business — not to ruin people’s lives." Is Alex getting that "huge adrenaline rush" from protecting Walmart's property? Or is he getting that adrenaline from having power over people? Because his desire "to move back to the field side, where we actually deal with people" seems to imply that it is the power over people that he craves and not the loss prevention.

as with most important things

Ever been in a store dealing with significant amounts of shoplifting, such as basically all chain stores in San Francisco these days? The more the shoplifting, the more stuff ends up behind locked cabinets. In some stores it's so bad even candy is locked up.

Now consider what happens when convenience stores stop being convenient. People with money stop patronizing them. They reduce their stock of items. They close. And now people, including poor people, no longer have a convenient place to shop.

Everybody has options. Shoplifting is very rarely, if ever, the best option available to someone on the ropes. It's just often the more convenient option, until it stops being convenient for them and everybody else.

I once saw a guy stealing a Moleskine notebook. Maybe that notebook can be resold, and he uses the money to pay rent?

Or more likely, he uses it to buy drugs.

So preventing the shoplifting might just save his life from a drug overdose.

It's hard to say that stealing is clearly right in almost any scenario. It's almost always anti-social.