I'm in Canada, and I assume you are in US?
Up here more companies got on the peanut free bandwagon a long time ago. I do think, overall, allergen labelling is better here.
Most catering companies that want to do schools, day cares, daycamps, etc., must be able to provide peanut safe food. Sometimes the entire company must be peanut free to get the contracts. Now, many of those places are also insisting the catering company be able to accommodate other allergens. So, when my son was getting married, he was adamant that his mom would NOT eat out of Tupperware, so he specifically questioned about allergens.
So, in this case, it was not a caterer doing anything special for me, it was finding a caterer that already does it all the time.