No, it's about an overly complicated solution to a problem that can be solved with much simpler means.
If the students are required to carry their school-issued ID, that school-issued ID can serve as their payment card, and if there's a concern with fraud in the sense of a different student using the card, then add a PIN pad to the card reader. Mind you, at least in the elementary schools the lunch ladies know who's on free and reduced lunch, who has special diets, etc, so it would be harder for fraud by kids.
Or, cross-link the ID card system's picture database to the POS in the cafeteria, so that when the card is swiped, the picture comes up on-screen, and the lunch lady can see if the student paying is the student on the ID.
And as for elementary schools, at least around here the kids come as a class, and many times the lunch lady simply points to the kid's face on the touchscreen as the whole class is on-screen at one time, so the kid doesn't even need ID.
This fingerprint system seems like an overly complicated, overly invasive means to cover a couple bucks or equivalent-pounds worth of food every day.