You are not obliged to receive ashes on Ash Wednesday. You are obliged to fast and not eat meat.
Yes, that would have been interesting to see what he had for lunch or dinner and how much.
The term “day of obligation” in common parlance refers to the obligation to hear Mass. It was in that sense that the commenter used the word and that I repeated it. Yes, indeedy, one is obliged to fast and abstain from meat on Ash Wednesday.
But that’s not the way the term is normally used.