I'm just over three months post op, and I'd asked my nutritionist the same question--should I be eating every two hours, because it's happening no matter how much Protein I manage to eat at a meal. Logically, when you can only eat 1/4 cup of food at a time, of course it won't last long. I'm now up to about 1/2 cup for MEALS--measured protein, a little side of veggies. Her response was that it's okay to have Snacks that are almost (ALMOST) the same size as meals--1/4 cup of protein-based snacks in between meals will not hurt, and it's almost required to get your protein in through the day. cheese, nuts, yogurt, beef jerky--as snacks, they satisfy and add to my protein count. From what she said, I think this levels out around six months--at that point, you can usually expect to eat more at a meal (up to a cup) which will last longer and cut the need for snacks.
Of course, every person (and probably every nutritionist) is different, but hopefully this helps. I know if I sit around and think about being hungry, I'll snack on things I shouldn't (post above is spot on) and it won't benefit me at all.
Good luck!