You posted that in Islamic religion, gambling and betting are seen as Haram. Gambling sites also know this and they avoid to relate with Muslim's festive celebrations. Or am I not getting it right? I have not noticed anything like that before.
Christmas and the Easter celebrations are symbolic for the birth and death of Christ, the Casino's know this, and are also aware that gambling is a sin in the religion of Christians, but they still do not fail to bring up Christmas and Easter events. Are you saying that Casino's are religion sensitive?