freebie
/ˈfriːbi/
noun
informal
A thing that is provided or given free of charge.
Origin
1940s (originally US): an arbitrary formation from free.
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In casino parlance, we were "comped" for our room charge. We got a
freebie. We lost our shirts at the blackjack tables, though.
In truth, my biggest experience with free stuff is the "swag" (stickers, T-shirts) passed out by vendors at technology conferences.

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Lexico offered the following word, but, as it is un-checkable, I took the liberty of using a synonym. I take lots of liberties. By now you must be used to it.
By the magic of tech trickery, though, you all get a double word benefit today.
lig
/lɪɡ/
verb ligs, ligging, ligged
[no object]informal British
Take advantage of free parties, travel, or other benefits offered by companies for publicity purposes.
‘instead of touring, the band spent all their time fighting and ligging’
noun
informal British
A free party or show provided for publicity.
‘I wasn't interested in ligs, or freebies, or expenses’
Origin
1960s from a dialect variant of lie, literally ‘lie about, loaf’, whence ‘freeload’.
Words are a game. Sometimes I play alone, but I encourage YOU to play, too.