The National Restaurant Association (NRA) signed an agreement to keep the annual convention in Chicago through 2016.
With cities like Las Vegas and Orlando offering cheaper rates to hold conventions and trade shows, the NRA was considering pulling its big show out of Chicago.
One union is challenging the new NRA-supported new state legislation.
The NRA convention, which has been in Chicago for the past 61 years, brings in more than 60,000 exhibitors.
With rising trade show costs at McCormick Place, the NRA was shopping around for a different city until the new state law passed.
The NRA has now committed to stay in Chicago through the year 2016. Governor Pat Quinn says the NRA is the ninth major convention to commit to Chicago since the new law was passed.
"Altogether, the amount of money expended by the nine conventions that have announced their expansion or extension is over $2 billion, and so we all understand that hospitality and tourism are a key part of the Illinois economy," said Quinn.
While lawmakers and convention operators are happy, some unions are not. The Carpenters' Union says the new law cuts its workforce, which has a big impact. Union President Frank Libby says 14,000 man-hours were lost during one show in August.
"That's a loss of revenue to the pension fund; it's also a loss of revenue to our health and welfare fund for insurance benefits," said Libby.
The union is legally challenging the new law, but Mayor Daley says that without it, McCormick Place might not continue to exist.
"This place would be empty if it wasn't for the changes that were necessary in Springfield, and I know it's hard on many people, but in the long run, I firmly believe this is better for all the members, better for the citizens and the taxpayers of the State of Illinois," said Daley.
The restaurant show alone generates more than $100 million each year.
Other shows that have recommitted to Chicago include the International Housewares Association and the American Academy of Ophthalmology.
This week, the American Heart Association (AHA) is in town. Its show brings in 24,000 people. A spokesperson says that the labor cost-lowering law will ensure that they keep coming back.
"We like Chicago a lot, and since we have attendees from all over the world, Chicago is ideal because people from Asia can get to Chicago easily. People from Europe can get to Chicago easily. And it is a great destination," said the AHA's Mariell Jessup.
The AHA comes to Chicago about every three to four years, alternating between different cities.
A decision on the carpenters' union lawsuit is expected in the next few days.