Is it tacky to take home leftovers you got for free at work?

I did the same at a class reunion. There were those Styrofoam boxes down the length of a table with the leftovers. Nobody made a move, and I was sitting at the one end of the table, so when my ride was ready, I picked up five or six boxes and took them home with me. When I did it, I heard someone make the remark about "Yeah, go ahead, take it home." I didn't care. It's terrible to waste food and I had a good variety for lunch for several days.