artist demo download free function homepage individual link listing next offer optional pages sale shop song totally turned

I just noticed that on some of the artist's individual pages, they offer a "download" link right next to their "homepage" link. Is that for a free demo of the song that's for sale? If so, can that function be turned off?

Listing on E-junkie shop is optional and even in that case it's totally up to you to provide a free demo download or not.