Yes. But you might have to get there early.
RoL: if there's two showings on the night you're there, then I recommend the second showing as it's a lot less crowded. If there's only one showing and you're doing standby, then I recommend getting there 60+ min prior to the show. Last time I saw it standby line was nearly at capacity 60 min prior to show
Fantasmic: earlier you get there, more choice you have in seating. I always recommend getting there 45-60 min ahead. I like to get there 60 min ahead because that's usually when they open the arena is an hour before showtime and I like to sit as close to the middle and front as I can. Fantasmic is also an easy show to get as a 4th fp.
Both shows allow food and drink inside, and Fantasmic has concession stands set up inside as well. Also note that when I say to get there 45min or so before showtime, that's 45 min before showtime but you're sitting in your seat, not standing in line