Robert,
You may think that others are sinning by engaging in innocent recreations in moderation (by “playing” at times), but has it ever occurred to you that in light of what St. Thomas Aquinas says, it is you yourself who could be the one who is sinning – by “playing too little,” as St. Thomas puts it. I know what Thomas a Kempis says in his book and I agree with everything he says in Imitation of Christ, but I will not disagree with St. Thomas Aquinas (a saint), and believe that neither he nor Thomas a Kempis contradict each other.
It appears one problem we have here is that you make ALL recreation equivalent to enjoying worldly pleasures. Worldly pleasures are pleasures that take us away from God, they are sinful and should not be engaged in – they are worldly and do nothing to help us supernaturally. Attending a football game for some can be very innocent recreation that makes them appreciate God and love Him more, like when people go to football games for family reasons and for good reasons (e.g. just to enjoy the goodness of the Lord’s blessings: rest on a beautiful day, fun entertainment for them, the company of wholesome friends, the enjoyment of wholesome competition and skill found in God’s creatures, etc… ), which is good for their soul, not harmful to it, like worldly pleasures. I am NOT advocating people attending sports events on Sundays and I am not interested myself in attending sports events for my recreation at any time; I just think we need to understand better the difference between worldly pleasures and innocent pleasures that can actually make some people appreciate God and love Him more. Worldly pleasures are not to be engaged in, as Thomas a Kempis indicates in his book; and I agree with him 100%. But innocent pleasures that do make some people appreciate and love God more can not be considered merely a “worldly pleasure” for they have the effect of giving glory and honor to God in the person who appreciates and loves God more by having engaged in them. Worldly pleasures can not have this effect. For example, If I were to sew because I like to make very fancy clothing for myself as my recreation so I can later show them off to my friends, this is not the same thing as if I were to sew for recreation to make Brown Scapulars for a mission. Clearly, we have the same recreation in both cases: sewing. But in one case it involves a worldly pleasure, in the other case it does not. What I am saying is that we need to properly distinguish worldly pleasures from pleasures that are not worldly; we need to understand the difference between good recreation and bad recreation which should not be engaged in. Is watching football a recreation that should be avoided? Is it always and in every case mere worldly pleasure to watch a game? I myself want nothing to do with the sport, but I think that good holy Catholics watching some football games from time to time isn’t necessarily a wrong or harmful decision, if they were to benefit in some good and supernatural way by attending a game. God bless you.