Vintage ;
mid-15c., "harvest of grapes, yield of wine from a vineyard," from Anglo-Fr. vintage (mid-14c.), from O.Fr. vendage "yield from a vineyard," from L. vindemia "a gathering of grapes, yield of grapes," from comb. form of vinum "wine" + stem of demere "take off" (from de- "from, away from" + emere "to take;" see exempt). Sense shifted to "age or year of a particular wine" (1746), then to a general sense of "being of an earlier time" (1883). Used of cars since 1928.
(
http://www.etymonline.com/index.php?all ... hmode=none)
And from Merriam-Webster ;
1 a (1) : a season's yield of grapes or wine from a vineyard (2) : wine; especially : a usually superior wine all or most of which comes from a single year
b : a collection of contemporaneous and similar persons or things : crop
2
: the act or time of harvesting grapes or making wine
3
a : a period of origin or manufacture <a piano of 1845 vintage>
b : length of existence : age
So as it seems the word is largely to do with wine making, really it has sod all use outside of the wine making industry and for someone to say something is vintage without giving a date of that vintage, then what they are doing is using an advertising buzz word designed to entice those seeking old stuff.
But if the OP is unhappy their purchases are not what they expected, one could give the vendor ear ache for not properly describing the items as vintage means nothing without that all important date.