Some restaurants are having specials on April 15th. Here are a few I have found so far, I will update as more are announced.
Starbucks : Bring in a reusable mug and get a free coffee.
PF Chang's- If you have a PF Chang's Warrior card, you will receive 15% off your meal, instead of the usual 10%.
Chic-fil-A -select locations maybe offering free 3 count Chicken Minis. Check with your local store to see if they are participating.
Whole Food's NO SALES TAX shopping in North Carolina, South Carolina, Tennessee, and Alabama
Maggie Moo's You can get a free sample of Maggie Moo's Icecream Pizza from 3 to 7 pm