While some of the above comments are valid others are well over the top and make one tend think one is not dealing with another form of human life.
I have lived in the real Thailand, not the tourist spots, for over 6 years now and married to a Thai lady, so have a good idea what it is all about.
There are some things you should NOT do and others that it is preferred you don’t do. There is a difference. Thai’s in general I believe are becoming more tolerant and understanding of the foreigner’s ways. That is not to say you should force your ways or views on them.
Your first comment is well over the top regarding the handling of money, yes you should never ever put your foot on the King’s head but other than that money is handled the same as it is in other countries.
The next item again is over the top. Noone should throw something at anyone unless it is for them to catch.
Regarding eye contact – never heard of or seen this as being something to offend the Thais,
though could be relevant to the Monarchy and those who think they are so much better than others.
Regarding your comment on drugs, and I don’t and have never used, there are more Thais using drugs than in many other countries and unless you are trying to sell or upset them because of your actions while being high, you will be left alone.
Regarding speaking to monks this is true to a certain extent but it is the older generation that knows how to converse in the different way. Monks are not great conversationalist as a rule so is unlikely to wish to have a long conversation with you. The younger Thais can talk to them as they would to family but always with great respect. A lot of the more elderly/senior monks can speak limited English. My advice is not to try to speak to a monk unless they start up the conversation. MY wife’s brother is a monk so I do know a little about this.
Regarding your comment on pictures, this is only the case if the picture is of a member of the Royal family or a monk.
Yes it is wrong to expect the Thais to do things as you are used to/expect in your country and one has to be extremely tolerant and learn to adjust and this is really not that easy. The last part of this comment should have been ‘it is the Thais country NOT yours. Basically saying if you don’t like it then go back to where you come from or to another country where the ways of doing certain things are similar to what you are used to.