This is great idea but not for everybody and not everywhere.
For example, in my country almost nobody know about Bitcoin and many people don't or can't use Internet often.
Also, people even don't use Internet often for financial transactions, Internet banking, buying or selling on Internet etc.
So, concept about Bitcoin is still very difficult to explain to them.
I tried with several of my friends but without results, they was very skeptic.
It's obvious that in some countries foundation for Bitcoin is much bigger than in other countries.
I like your idea about World Bitcoin Pizza Day and wish you every luck- but it's to early to try something like this in my country.
Its not my idea mate, but i do think we need to start acting as community when it comes to bitcoin awareness,
which is why i suggest we start making an effort to celebrate these historic days for bitcoin in an effort to make others aware.
and this can be for everyone everywhere, how about you make May 22nd the one day that the only thing you must do that day, is show someone bitcoin and give them some, that itself helps, you just need to find one person with a smart phone, install mycelium and give them a few satoshi.
Every little helps and we need to act as a community and stop making excuses like i cannot explain what bitcoin is because people dont know, thats exactly why we need to explain, i understand it may be too much for some, but nobody expects anyone to go and convert a nation over night, but we need to make more effort as a whole. Speak to those that have more of a reason to be interested like a business owner first instead of those who got more important things to think about like people more concerned about putting food on the table.