People are shopping and browsing at outdoor vendors.
People are shopping at an outdoor festival.
The outdoor vendors could easily be at another event besides an outdoor festival.
exists e2 e1 s1 s2 x1 x2 x3 x4.(at(e2,x4) & n_vendor(x4) & a_outdoor(s2) & Theme(s2,x4) & Actor(e2,x3) & v_browse(e2) & n_people(x3) & at(e1,x2) & n_vendor(x2) & a_outdoor(s1) & Theme(s1,x2) & Actor(e1,x1) & v_shop(e1) & n_people(x1))
exists e1 s1 x1 x2.(at(e1,x2) & n_festival(x2) & a_outdoor(s1) & Theme(s1,x2) & Actor(e1,x1) & v_shop(e1) & n_people(x1))