Everyone should be treated with respect until they prove they don’t deserve it
They proved they didn't deserve respect by flying with airlines which are infamous for treating staff poorly, ignoring and outright breaking labour laws, regularly fucking over customers, and by flying relatively short distances rather (than taking a train, bus or even car) and being part of the problem when it comes to climate change.
Obviously, I know this is a hard truth, but if someone sees a kid drowning but chooses to eat an ice cream rather than help they're evil. Most people do that on a daily basis because the kid's drowning far away and off-screen. Why should underpaid employees have respect for customers who support a company that fucks people over, when its their turn to get fucked over?
They could instead earn some respect by buying a ticket with a regular airline that treats its staff properly, or by taking the train because although it takes a bit longer you're not killing the planet.
then you probably shouldn’t be working for a cheaper airlines
Most groundstaff work for a handler, not the airline itself. So in this case the cheap airline subcontracted my company to board and deboard the plane, take care of luggage etc. But crucially, the cheap airlines didn't pay us to handle complaints or deal with delays. So when a flight was cancelled, as often happened because they knowingly flew a schedule which was far too tight, customers would be left stranded and be told to call a call centre somewhere on a paying number. Once again, it's hard to sympathise, given these customers knew that this happened regularly, yet still went ahead and bought the cheap tickets anyway. We would however hand out little fliers and explain their rights under EU law. Said airlines would regularly flout the law when it came to legally required compensation. Obviously that's no different in the US.
In any case, you get what you pay for. Of course, this was only a short term starter job. They didn't pay enough to retain staff long term. This is common in the industry, which is why you'll occassionally hear stories about a kid sneaking past the gate and end up in the wrong destination or someone getting sucked into an engine. Staff would turn up drunk or high, not bother to check documents properly, not enter the weight of luggage correctly leading to balance issues, that kind of thing. You pay McDonalds wages you get McDonalds level employees. Have a safe flight!