Businesses, especially big businesses, try constantly to shift work from their paid staff to their customers. It's one of the major trends in business today.

Customers are willing to do the work when it saves them money or saves them time. They're delighted to do the work when it makes it easier for them to get exactly what they want--selecting their own fruit at the grocery store versus having a clerk give them a bag that includes one bruised piece that otherwise wouldn't sell.

Business will go to great lengths to get you to do unpaid work (same as to get you to buy stuff in the first place). They'll gladly pretend that it's an "improvement" in service for you to do the work yourself--a claim that's even true sometimes, as when you can look to see if a check has cleared on your bank's website, rather than having to get an employee to look for you. They'll pretend it's more convenient to do it yourself than to wait in line (and then they'll get rid of some employees to make sure that the lines don't get shorter). They'll even try to convince you that doing unpaid work for them is a moral issue.

When I was in sixth grade my elementary school class took a bus trip to Chicago to visit some museums. We brought brown-bag lunches to eat on the way, and before we went our teacher carefully coached us about gathering up our litter and throwing it away, so as not to leave a mess on the bus. When we reached that point, though, the driver used the PA system on the bus to give us alternate instructions.

Finished with your lunch? Put your trash back in your bag. Now, stuff the bag underneath your seat. I know the guy who cleans this bus. He's got a family to support and he needs the work.

That made a huge impression on me, and not just because I'm the sort of lazy person who will seize on any excuse to avoid cleaning up after myself.

When I'm hiking in the wilderness, I'm scrupulous about packing out my own trash. When I'm in a genuine public space--walking on the street or in a park--I use the trash containers provided. But I'm much more dubious about the matter when I'm in an establishment that hires someone to keep the place clean. When I leave my empty popcorn bag on the floor of a movie theater, I figure I'm helping save someone's job.

The general trend is probably unstoppable. There are so many cases where it actually is more convenient to be able to do the work yourself, that the cases where it isn't get a little hard to spot and a little hard to resist.

Economists would have you believe that the free market will take care of the matter: Customers will give their business to whoever provides the best service at the best price. Keep that in mind, when you decide whether to do unpaid labor for the convenience of businesses.