Online casinos can cause some problems also. They may run away with you money. Or their systems might be fixed so that they keep all the profits. This is quite common with websites offering card related games online.
Business is business and no matter whether it is online or land based, the owner is always trying to get money out of customers pocket. If this was not the case then I am afraid people would not have any interest in establishing their own business or these people would have been poor. If a gambler is of the opinion that online gambling is done with honesty then he is fooling himself only. There is nothing like honesty in this world.