Really the people had already decided that Jesus
was the Messiah. The miracle of the loaves and
fishes had fully convinced them of that. But they
were, of course, were thinking of a different kind
of Messiah. One that would feed them with manna
like Moses had. (John 6:30-31). The miracle
of them being feed by Him the day before made
that clear.

But they wondered why He had evaded them
by going up into the mountain; because they
were ready to make Him king. They were
wanting to get an answer from Him.