I have heard of crew,both cockpit and cabin crew of many airlines resort to cooking their meals in the hotel rooms while at outstation.
The reasons varied from one individual crew to another.Some cooked in the rooms because they were not used to eating the food sold in the countries where they nightstopped while others did it for economic reasons.
Whatever the reasons,it was not encouraged by the hotels. Firstly, the rooms if not cleaned after cooking would attract cockroaches or rats. Secondly,it could be a fire hazard and thirdly,after all the discount the hotels had given to the crew (agreed during the signing of the contracts),they expected the crew to patronise their food outlets.
To the hotels,another kind of cooking that contained spices eg. curries or cooking with ingredients which were strong and "pungent" were also discouraged as the lingering "odour" could offend other guests.
There were cases where crew had been disciplined by their respective airlines for cooking in hotel rooms. Some burned the carpet floor or wooden tables as a result of their carelessness. Other splattered the walls with gravies of curry,stew,tomato and chilly sauce etc.
Another popular "pastime" was the "hijacking" of paid movies and watched them for free on their television sets.They usually stripped off the little magnets on the hotel closet doors and stuck them somewhere on the inside of the television sets. In this way,one could watch all the paid hotel movies for free.
One cheapskate crew was caught for replacing the hotel room light bulbs with his owned fused bulbs which was brought from home.
There were a few cases of crew,after consuming the alcoholic contents of the miniaturised bottles in the mini bars,refilled them with colored water.One even filled the empty bottle with urine .All of them escaped payment when they checked out.
Cases of crew stealing bath towels,pillow covers,coffee cups, teaspoons were common.
However,the most bizarre was the loss of a full length curtain by a hotel on Queensland Gold Coast.
There was another crew who almost got electrocuted because he inserted a penknife into the bed massage coin box to get a free ten minute massage in a Hong Kong hotel.
There were and are many more mischievous and sometimes, malicious and destructive acts committed by the crew which I am not able to recall at this moment.