Sugar daddy/momma relationship

My sister just recently entered a poly relationship with a 35 year old man and a 27 year old women. She's almost 26 so this is okay. The couple she joined is married and has a 14 year old daughter, that part I'm a little iffy about, but it's really not my decision.

She's known these people for less than a year and stayed with them for a week last month, that's the first time they physically met. These people live 3 hours away from where she was living, now she's been living with them for a 8 days. She helps out the women with whatever she needs while her husband is at work. They are giving her $500 a month. I joked with my sister that it's a sugar daddy/momma relationship and she got all pissy and now she isn't talking to me, which is fine cause we were obviously disagreeing. I mean it kinda is. Just because there's actual feelings and affection involved doesn't mean it's not a sugar situation. She said I insulted their relationship. They are literally giving her an allowance for helping the wife cook and clean, with the wife doing the majority of it, so basically doing nothing.

They pay for everything. Her doctor appointments, her food, housing (since she lives with them), and they even drive her places since she has fines she needs to pay for she gets her license back. 100% dependent on these people who are basically strangers. They paid in full for her trip last month when she visited. They paid for her to come back and said they will pay for her to go back home if things don't work out. I'd call that a sugar daddy/momma relationship wouldn't you? Even if she was actually getting paid for her work, $500 a month is $2.88/hr

This is my sister's second poly relationship, the first one only lasted a month and she ended up breaking them up because there was a lack of communication. Their was kids involved in this one too so the kids will now have to lives back and forth. Before that she has always been in toxic relationships. She moves way too quickly. If she's in a long term relationship she wait 3 months until she jumps to the next one. Not to mention she got married at 19, separated at 23(not divorced) and just keeps jumping from relationship to relationship. She told her 'ex' that she might want to get back together with him one day which is why she doesn't want a divorce.

Yes I'm judging, no I don't linger on it cause she's not worth my time or energy. End of rant