I agree with you most wholeheartedly. I travel with a High Sierra backpack and a very small carryon. If I buy giftys, they are things like jewelry that take up little or no space and weigh very little.
Should anyone ever venture to Paraguay, they make some beautiful silver filigree jewelry in the town of Luque, near the Asuncion airport. There is nothing like it anywhere else. They also have beautiful ñandutí (spider web) lace tablecloths, veils, mantillas and such.
In South America, the souvenirs are all locally made: no Chinese manufactured schlock with 'Miami Beach' written on it. I can't remember when I have seen American made souvenirs: maybe back in the 1950's, they had things made of alabaster and cedarwood.