Some random dude walked up to me while I was waiting outside a food place for my food and asked me this question.
I said “no, I dont give out random favors” and something along the lines of that’s sus.
Is it rude to say no to random dude that asks for a favor?
As some others have said, no, it’s not rude to decline. Whether or not it’s rude is in how you word it. You were rude in this particular instance.
The question is rude in this context. It’s not rude to completely ignore rude questions.
Your rationalization sounds like some self centered manipulative bullying bullshit.