“Moshe Rabbeinu did not consider it “fine” when the Yidden in the midbar asked him for things!
Seeשמות ט”ז”
The problem there was that they were complaining, not
asking. And so Moshe was upset with their lack of emuna.
Interestingly enough, you’re quote proves my point exactly. Moshe is saying there that when they complain against him, is not against him as a person, because what is he? He had no ego / selfish interests of his own. Rather, when they rebel against Moshe, they are really rebelling against Hashem. Because Moshe is just the messenger…