Teresa,
LCC are holding the upper hand at the moment because of the (relatively) low oil price. Remember the "golden" period, just before the GFC meltdown when oil was well above $100 a barrel? It was the LCC segment that was really hurting then because their passengers are the most price-sensitive. For airlines to maintain a profit, they had to increase the seat price (through fuel surcharges).
Have you noticed since the GFC bottomed-out, that any increase in the stock index is nearly mirrored by the oil price? I reckon that when the world's economies are booming along again, that the oil price will be way up there again. It will then again be the LCCs that will be hurting - those that can wear a higher seat price will pay more while those who can't won't travel. Jetstar will probably be more affected by this than Qantas - as they were before the GFC.
I flew with a Captain when oil prices were very high who said that he foresaw a future where airlines were deprivatised and reregulated, and air travel was once again the province of the wealthy or powerful - this version of the future is very different to yours, Teresa. But how long can airlines sustain low fares if the oil price increases? How long will the world's financiers continue to fund airlines re-equipment plans when the industry continues to lose billions of dollars every year.
I think the worm will turn. LCCs are being used in the short term by airline management to provide cheap fares through the slashing of staff wages and conditions. With a very high oil price, it will (I believe) be again a very different market for LCCs. Hopefully the "legacy" carriers can withstand the current cycle, before airline management around the world essentially redefines industry payscales through their low cost (low-wage) carriers.