I like those last two. I don't ever go to restaurants at lunchtime but my wife travels and hooks me up with cool stuff. Actually, if you think about it, calories is calories and condiments aren't necessarily more weight if you figure them into the equation. The ones that I tried to find to send my buddy in Iraq was Miracle Whip and Hellman's Mayo not that fake shit they sent us when we were out in the bush for our once a week 'hot' meal, tired and ready to buttstroke the clean truck driver.
Honey: Starbuck's (real honey), fried chicken places, other fast food such as fish shops - though some are flavored corn syrup. Read carefully. Butter and its imitators: fried chicken and fish shops, other fast food, continental breakfasts, diners. Ketchup & mustard: Your favorite fast food place, grocery store delis. Salsa/picante sauce: Fast food that offers burritos and convenience stores, sometimes you can find 4-8 packs of tubs at grocery stores and Quickie Marts. Ranch tubs: Fast food and Hidden Valley Dressing® in 4 packs at the grocery store. Parmesan Cheese & Red Pepper Flakes: Costco and Sams Club food courts, any pizza joint. Jam packets or tubs: Fast food, continental breakfasts at motels, diners. Soy Sauce & sesame seeds: your favorite Chinese place or full service grocery store deli. BBQ Sauce: fast food. Salt and pepper packets: most places. Mayonnaise and relish packets: Convenience stores that sell fried foods, deli's in grocery stores, truck stops, sandwich shops.
Arby's® is great for Horsey sauce, their BBQ sauce, etc.
Many McDonalds® and KFC® have moist towelettes in packets.
Papa John's®: will sell you tubs of cheese sauce, garlic sauce, marinara sauce for minimal cost. They also have Parmesan cheese and pepper packets.
Visit PackitGourmet and/or Minimus. These companies stock so many items you will want to order as many as you can. They carry many hard to find items. Minimus also carries supplies for stocking your first aid kit as well. Both have excellent customer service and are fast. Now go shop!