One word can have several meanings, or many different shades of meaning, and advertisers can use this to give a misleading impression of their product without actually breaking the truth.
I'll give you a silly example. Our staff restaurant recently had on its menu "vegetable soup with fine herbs". I bought some, thinking that "fine herbs" sounded very classy. As it turned out, the herbs were of an average quality but just chopped up very small. Fine can mean both "high quality" and "consisting of small particles" (OED).
Of course, these two meanings of 'fine' are related - fine jewellery, which has "delicate or intricate workmanship" (another OED meaning of fine), is probably of "high quality". There is an association between being small and delicate, and being of high quality - which, sadly, isn't true in every case, as my vegetable soup showed.
All these meanings of fine have the same origin - the Latin word 'finire', which also gave us the English word 'finish'. So we're not talking about several different words that sound the same (known as homonyms), but one word with several shades of meaning. And this is exactly the kind of thing that advertisers can play on, so beware.