I wrote the Intellivision Mattel Roulette cartridge game back in the 1970s. It was all in assembler on a 10 bit (!) CPU. In order to get the game to fit in the ROM, you had to do every feelthy dirty trick imaginable.
A friend of mine wrote the Mattel Intellivision poker game. I was playtesting it (a very boring job), and got suspicious. I walked over to his desk and said the program was cheating. It was looking at my hole cards. He sighed and asked how I knew, and I replied it was obvious. He said he didn't have room to add code to improve its play otherwise. I don't know if he fixed it or not.