Trash or treasure...who decides?

Looking to pieces that have been deemed as “art,” why is it that we all see pieces such as the Mona Lisa as definite works of art? Simply because we have been told so by the so called “professional critics” and because they hang in world-renowned (what does that word even really mean…another societal acceptance perhaps?) museums like the Louvre?

When looking upon a pile of trash we typically would just see it as trash; but when an artist such as Frank Galuszka comes along and paints a picture of this pile of trash, giving it some sort of meaning—the decay of society—then it is suddenly deemed art? If this is the case, then nearly anything in the universe—tangible or imagined—could be seen as art…as long as you can get the “professional critics” to accept it as such. Is art just a play on acceptance and/or approval? And if so, is this acceptance/approval really only in the hands of a few select people?

It seems to me that art should be universal, allowed to be accepted/approved by whomever creates it and/or whoever views it. As the popular saying goes, “beauty is in the eye of the beholder.” So who has given these “professional critics” the ability to determine what I see as beautiful or, for that matter not? Isn't it the point of art to allow for separate interpretations, especially when it comes to such an abstract piece like that of Galuszka's Out of this planet. Shouldn't art be in the eye of the beholder--whether beholder is viewer or creator--and not left to be determined by the 'learned' graduates of art schools.