That would be worth it if that were true. Did you play slots or VP?
I used to do that sort of thing many moons ago on the Strip, back when they still had decent games. For instance, a couple of hours of ten-play .10 9/6 DDB (98.8%) at New York New York got me $500 free play every month for six months. That was ridiculous.
You're not the only person I've heard of who's gotten disproportionate comps from some modest play. I think you're more likely to see that now when the casino isn't one of those megablob corporate places like a CET or MGM property. Wynn might be actively courting players to counteract recent negative publicity.
Definitely go there and take advantage. Have the buffet three times. Be sure to stiff them on play--there's no chance you'll be rewarded as lavishly next time. They're just testing to see if you're a standard sucker, and if not, well, the rooms and food didn't cost them all that much.