The 는데 ending hangs a setup on the first clause and leaves the point for the second, which here is about eating. In most of these lines the two clash: they saw all those places but could not eat at any, he knew about it but never got to try it, he ought to eat but does not, he wants to grill it but has no time. One line runs the other way, where the food is being offered so of course he will eat it.