I would think God could have been tad clearer for something as important as that.
Or we (the Church) could have picked up on the truth much sooner than we did. (It took centuries.) God is patient. He understands it takes mankind a bit to catch up to Him. 
I think formal holidays were developed along with missionary and propagation efforts, so as to provide structure to the lives of new converts.
Cutting down on formal holiday schedules, tends to relax the quest of proselytizing and increasing number of believers.
It would be nice if we still had some of the old school Latin people visiting the boards. Maybe their was another definition of the word that was being used. Instead of being morally bound to go it meant that people were restraining themselves from what they would normally do to attend mass.
The short answer is, we must attend Mass on those days.
The long answer goes into the subject of “authority” which is the root subject of every Catholic-Protestant debate on every doctrinal subject. Once the dust settles after every argument the final question is, who has the “authority” to decide doctrine: The Church or each individual.
As for this topic, the Church has the “authority” to proclaim Holy Days of Obligation, according the the Church.
And if you want to be Catholic, you cede that authority to the Church, else what’s the point in wanting to be Catholic in the first place?
Well, its slightly more complicated than that. The argument goes: Jesus gave authority to the 12 apostles, and they in turn gave it to those who they ordained, and so forth. Therefore authority lays with the men Jesus chose, not with each individual disciple making up his own personal beliefs.
The catch is, tracing that line of authority from Jesus to todays Catholic bishops. They say there is an unbroken line from Peer to the Pope: CATHOLIC ENCYCLOPEDIA: List of Popes
In a sense that’s what I was saying. (Or attempting to say.) And that Apostolic succession is why Catholicism claims its Authority. Either a Catholic believes it, (and cedes authority to the Church on that accord), or the person shouldn’t want to be Catholic. (And such a person, by rejection of that tenet, self-excommunicates him/herself.)
Yup. And one professing adherence to Catholicism must accept that authority. If not, there are plenty of other faith expressions that would be more aligned with his/her wishes.
I think it is simpler on the Protestant side.
Just make a good faith effort to show up on Sunday morning. 
