Everton lost 4-3 on aggregate.
Moyes believed the German referee Peter Sippel should have handed Liege’s Steven Defour a red card after screaming in the face of the official.
Sippel almost came into bodily contact with Sippel during the incident.
“You can’t run up to a referee and do that in his face nowadays. I thought they were stricter in Europe,” he said.
“I thought he should have been sent off for his reaction and then for him not to be sent off for the professional foul on Yakubu was unbelievable,” Moyes added.
“I think the crowd were very good for Standard. They influenced the referee – they did a very good job.
“If he (Defour) had been sent off it would have made a difference because he had the shot that led to their first goal.
“We were playing well against 11, so against 10 we would have had more space. I think it (a dismissal) would have made a big difference to the tie at that time.”