I used to think chain restaurants were pretty vegetarian-friendly. Then we had an office party at Applebee's, where even the salads all have meat.
For future reference, what chains have a good veggie selection? Bonus points if it's somewhat healthy.
Nothing: Chilis, Applebees, Don Pablos, Cracker Barrel, Red Lobster, Joe's Crab Shack
Hit or Miss: TGI Fridays, steak houses/barbecue places (call ahead - won't be interesting, normally a salad, gooey sandwich, or overcooked pasta primavera, but it's okay once in a while if every one else is happy ....)
Large selection: Bertuccis, CPK, Red Robin (veggie burgers), Ruby Tuesday (salad bar & veggie burgers), Pizzeria Uno (soup, salad, entree, sandwich, pizza - all really high calorie though!), PF Changs
Not all that healthy, but you can take any of those burger concoctions on the menu at Red Robin and substitute a Gardenburger or Boca patty for the normal ground beef one. Good if you're in the mood for a veggie burger because there are more possibilities for preparation than just plain-ish. They also have a couple of other possibilities on the menu that are veggie, although you can mark them down a bit because many of the appetizers have meat that can't be removed (even a spinach-artichoke dip that rather inexplicably from a veggie point of view includes bacon).
Most of the Mexican-oriented chains would be okay, but again not that healthy. Ditto the Italian ones. Whether the food is worth it is, as always, debatable. It's been some years since I was in a PF Changs, and only the once, so I can't remember but that sort of food should be at least somewhat veggie friendly, and capable of meat being left out of various dishes if desired.
There's not much creative vegetarian fare at the national chains, but a few may be helpful in devising an option if you ask. (Finding the proper decent service can be tricky, though, as it's so variable.) I don't count salads at all. I'm not veggie myself, but I eat out with someone who is.
I worked at a Big Corporate Firm for 10 years (6 of those as a vegetarian). While I was there we had office parties at Applebees/TGIFridays/Olive Garden....and the food was always overpriced and pretty unsavory, with few options for veggies.
We started going to some local mom and pop joints (usually Italian) and had better luck. Prices were actually better, food healthier, and more veggie options. I always gave some menus to the Office Manager (who organized the parties) and she'd take it from there. The mom and pops are more flexible with the menu and atmosphere is usually better. Good luck!