what are door gifts?

In my mind door gifts are something like the mini boxes of cake on the table when ur seated, never got anything that could be kept before.

but like a previous forummer said, I think it's a waste of money because it'll b thrown away, but u don't provide then they will say u're stingy.

I've seen door gifts (or at least I think that's a door gift) a cute little macaroon, with the initials of bride n groom on the surface, quite nice, cheap, meaningful, n tasty!