I don't see any problem there. Its true that we shouldn't gambling in front of children as it may effect them badly. But when its comes to mature people like you and your wife, there's nothing wrong until both of you guys can control yourselves, follow the discipline as well as able to manage economical status and become so responsible as gambler. Nobody need to quit, just mainly focus on primary income source and do gambling less or stay within limit. Don't spoil family moments , only gambling when get free time or children aren't around you.if you guys can't handle and worry about Ensure the healthy environment for children, then both can quit gambling together, otherwise there'll be a quarrel between you about this matter. So that is my suggestion
One of the parents just needs to limit the gambling habit because there is no way both parents can be gambling and be careful enough that the children won't come across them one day, which will draw their attention, and they might want to try it out someday when there is no one around them.
Another thing again here is that if a husband and wife are gambling, who is going to advise who on how or her gambling habit is? When I know you are also doing the same thing that I'm doing.
Another thing again is that when two people who are into the same thing are in the same house, you can easily start a conversation regarding that, which might last a long time, and gambling most times can lead to little disagreement when both parties are trying to prove that they have a better opinion or their fan club is the best, which the children can also notice such behaviour in them.
Some persons still do not know that gambling can be hereditary and we can inherit gambling interest from parent. If one of the parents are gambling addicted, that is quite understandable but when the both parents are gamblers, it could have serious effects on the children and there is no way the children will not be exposed to it. Children are always taking there parent lifestyle especially when they are small. They would want to mimic there parent especially if what there parent interest them. There are some certain things we don't have to allow to happen in any relationship we are so that the worse will not happen to us.