Christina Welsch is young, dresses conservatively, and is usually alone when she flies.

Maybe that’s the problem: She just looks like a babysitter.

On several occasions, she says, flight attendants have asked her to keep an eye on the unaccompanied minors flying that day.

“I like children,” says the Ph.D student, “so I’m usually willing to oblige. But it surprises me that this is an issue at all. Surely airlines themselves should have employees more focused on this task.”

They should. Not that flight attendants are babysitters (ask them to oblige with one of your kids, and you’ll probably get an entirely different reaction). And yet their airlines collect hundreds of dollars per child to ensure junior gets to summer camp safely or that his stepmom can pick him up from the airport in Pittsburgh.

They don’t always do it well, mind you. Just last week we heard about how United Airlines lost a 10-year-old flying from San Francisco to Grand Rapids, Mich. (I wonder if she’ll get her fee refunded?)

Welsch is among a small but growing number of passengers who are troubled by junk fees for which people essentially get nothing. That should bother anyone who travels, come to think of it.

For example, on a recent flight from New Delhi to London, a British Airlines employee at the counter asked Welsch if she would be willing to sit next to and “look after” a young child.

“She arrived — never having flown before — without anything at all to do and immediately panicked upon watching the safety demonstration,” she remembers. “I asked for assistance from the flight attendants, but I was ignored.”

Adding to the confusion was the fact that the girl only spoke Hindi.

“I did not speak sufficient Hindi to have a conversation with the child,” she recalls. “But I was able to entertain her — for the next nine hours — with some paper and colored pens in my bag.”

I asked British Airways about Welsch’s stint as an unpaid babysitter. A spokeswoman denied the airline asked passengers to look after unaccompanied minors.

“Our highly trained cabin crew take the responsibility of caring for these children, whose safety and security has been entrusted to us, extremely seriously,” the spokeswoman said, adding, “There is a specific seating department which has a range of guidelines to ensure that we place in an appropriate seat and on some services, this will be in a specially created unaccompanied minors zone within a short distance of the cabin crew in the galley.”

That sounds nice, but experience tells me that airlines often treat unaccompanied minors like minor inconveniences at best and profit opportunities, at worst.

Enlisting the help of passengers to “look after” these young customers — if it’s true — would be the final insult. Not only does an airline not want to be bothered with flying unsupervised kids, but it wants to take our money and ask us to watch after them.

Come on.

Some airlines already place significant restrictions on unaccompanied minors, limiting their age, the type of flight and their seating. Shouldn’t they also make it crystal clear to the rest of the passengers that the $100 fee Mom and Dad paid covers the cost of the flight attendants — not other travelers — doing the babysitting?