High insulin doses, whether endogenous or exogenous, cause insulin resistance. We can't ignore that fact.
Meaning if you eat high calorie meals and take more and more insulin to maintain stable sugars, you will eventually get IR, caused by weight gain (insulin literally makes you gain weight, by converting glucose to fat). I suggest people read Dr Jason Fung's blog posts on the subject of what causes IR: high calorie diets.
I checked on the recommended diets section for this website, btw Azure, and I saw no subforum for high-calorie + high-carb + high-fat diets, which is what eating pizza and french fries qualifies as.
A single slice of pizza has these nutritional values (taken from google):
Nutrition Facts
Pizza, 14" regular crust
Amount Per 1 slice (107 g)
Calories 285
% Daily Value*
Total Fat 10 g 15%
Saturated fat 4.8 g 24%
Polyunsaturated fat 1.8 g
Monounsaturated fat 2.8 g
Trans fat 0.3 g
Cholesterol 18.2 mg 6%
Sodium 639.9 mg 26%
Potassium 184 mg 5%
Total Carbohydrate 36 g 12%
Dietary fiber 2.5 g 10%
Sugar 3.8 g
Protein 12 g 24%
So pardon me when I see advice on a type 1 thread suggesting that eating an entire pizza is perfectly acceptable diet choice for other type 1 diabetics, so long as enough insulin is taken, I have to shake my head and call a red flag on that one.
There is no suggested diet that says eating high-fat, high-carb AND high-calorie foods are good for even healthy people, let alone a type 1 or type 2 diabetic. That's absurd.
You can go vegetarian which isn't necessarily low carb but it's low calorie and low fat, or low-carb / high fat which still counts as low overall calorie, or low-cal or fasting which all have as their lowest common denominator: low overall calories per day.
That is the crux of my objection to the idea of "just take more insulin and eat whatever you want". Eating high calorie, high-fat, high-carb meals isn't healthy, in general, for anyone, let alone diabetics. The data on that type of junk-food lifestyle is overwhelming and this is not really up for subjective opinion or debate at this point, I believe. I just find it really disappointing to read this kind of thing for type 1s here. I mean, seriously.