"healthy" and "take out" / "eat out" methinks are all but mutually exclusive terms.
well, except for strange and unusual food establishments - the std fare is: more salt, more fat, more better taste. so pipples like it and come back. . . .
there are, as pointed out, any number of options for "pre-cooked" foods morphed into (essentially) cold plates that one can consider for summertime "cool meals"
rotisserie chicken - if you take the skin off (that removes most of the ueber applied salt . . .) and slice for a salad, works fine.
one of my favs is a loose interpretation of Cobb Salad - I get the deli section to slice 1/4" thick slabs of ham & chicken/turkey - then julienne them into strips for the salad. low salt / low fat is a usual option at the deli counter for "lunch meats." hard boil some eggs, chop up some lettuce, tomato, onion, avocado - make up some bacon bits if you'd like - can be made in a size for a whole meal. bread sticks / grissini / reheated rolls (I've found Rhodes brand pretty dang good) - biscuits - whatever, make it complete. I find the chopped egg essential - but as to the bacon bits, some chives / parsley / fresh herbs make for a just-as-tasty salad.
smothering it all in a pre-prepped high fat, high sugar, high salt "salad dressing" - well, if healthy is the aim, that kinda' defeats the purpose. but a vinaigrette works and frankly I find it more "refreshing" than the commercial stuff.
whether buying it cooked or steaming a couple chicken breasts is easier/harder - that's in the realm of personal preference.
can pizza be made "healthy?" potentially somewhat "less bad" but cheese is the downfall.
the dough - flour, water, yeast, salt - most call for about 1 tblsp of oil per 10" crust . . . really isn't so bad.
going sans ultra-fat pepperoni - try a low fat pepperoni/turkey pepperoni (heh - it's turkey, but it's not bad!) is one option.
the sausage options would be not a good one.
onion, peppers, mushrooms . . . what's not to be good about that?
presuming the tomato sauce isn't 30% oil/fat, a vegetarian pizza should be reasonable except for the cheese.
cheese is, by definition, a high fat food. if you've ever tried to make a pizza with low fat cheese . . . okay, it's a pizza, tastes like sawdust on toast.
I should add, I rarely eat pizza except for my homemade variety - my dough, my homemade sauce - not drowned in "oil(s)" of highly questionable origin....
the old "assemble and drizzle with oil" routine is, for me, absolutely not an option. I put the "toppings" on first, then the cheese. when the cheese melts down over the toppings/stuffings/fillings, that's more than enough "grease" for me.