This sounds like a different problem than the one this post is about. For baby-in-lap, no one is being guilt tripped into switching seats because the baby doesn’t have a seat.
If you’re being guilt tripped into switching seats so that a family with a young child can sit together, consider blaming the airline for not automatically seating a young child next to their guardian.
Blame the airline for not automatically seating people who buy tickets together... together. It's just a trick to get travelers to pay extra.