I am aware that I may look at this from a very "european" perspective, where the airlines are in any case obliged to provide you with a hotel night and meal vouchers if a flight is cancelled or delayed overnight and ADDITIONALY, if it is their fault, they also are obliged to pay compensation of up to 600 EUR per passenger.
After reading this thread, AA was therefore correct to tell to my +1 that has been stranded in MIA yesterday night because AA2008 to EWR has been delayed from 9:40PM to 6:00AM that she will neither receive a hotel voucher nor a meal voucher as the delay has been caused by bad weather in EWR? Interestingly, all other airlines were operating out of EWR just normal yesterday evening. As she is not a very experienced traveller, she ended up sleeping on the floor next to the gate and is now hoping that the flight will actually leave in 40 minutes. I guess not much we can do about receiving any kind of compensation or voucher even if the "bad weather" excuse seems to have been a lie (see below: all other flights arrived normal to EWR)?