Im not sure if you are being sarcastic but the gemara would certainly not condone child dumpster-diving. In fact, Rav Adda was telling his wife to go find cheap food for his children to eat as the conversation was between him and her- no child labor. He was not telling his children to do so. Also, according to Rashi’s second interpretation as well the food mentioned had to be processed and baked.
I think the point of this specific gemara is that for some families (not all) it is ok to “rough it out” and live at the poverty line for the sake of Torah scholarship. Though it is true that he never said to go take tzedaka. I do wonder if that would also apply in a prosperous secular society with the advent of advanced machinery and technology.
I suppose also this would only apply to people who learn as sincerely as Rav Adda. Most people who do not have that aptitude should work several hours instead even according to that gemara.