Thoughtworks Senior Developer interview questions

was in the process of hiring for the position since a month which I gave interview today and was very much excited. But I faced a humiliating experience today (courtesy the house keeping staff behaviour). After giving my peer programming , HR requested to have lunch and then when panels will be available we will start with the interview. I had a good lunch and then went to put my plates, housekeeping manager or may be he would be housekeeping representative asked me to empty the food in trash , which i did (as we usually do everywhere), then he sort of ordered me that you need to clean the plates well in first basin with water then put it in the second basin. As , I in my whole experience or in my academics , i never faced situation where you are asked to clean plates(i felt a bit bad momentarily, but quickly thought it may be for everyone). In my mind ,, i was thinking of the next interview though I just casually replied housekeeping guy "I am not sure this would be done by housekeeping" . I dont know why this housekeeping guy felt so bad, and he said twice "this is done by everyone here" etc... i just said ok and acknowledged away thinking of my interview. He then discussed with one employee , then maybe went to HR. Meanwhile I drank water and the moment i came to meeting room , apporv came and replied me that you have talked very rudely to him and you got very angry etc... I said sorry to HR that may be he felt something bad , but i didnt meant something like that , as i was just thinking of interviews. HR was also like fumed off me.    Then he said that the decision has been changed and you were not good with designs and gave some reasons and we would not go ahead with candidature. This is the way they treat the candidates,the cafeteria guy can go and complaint about false and irrelevant things and hr will take action and revert their decisions and will talk in unprofessional manner. So, better be aware before going there.