The only reason I can think of is that the schedule has already been determined, so by looking at the schedule now (in the present), it can be seen that no games will be shown next Monday.

Judy's answer makes sense. I just wanted to add that I think the tense is awkward. Even the first part of the sentence is strange. I think it would be clearer to write: "... in the U.S, football games are usually shown on TV on Mondays, but no games will be shown on Monday. (The comma is quite necessary.) or "Although in the U.S. football games are usually broadcast on Mondays, this Monday no games are scheduled to be shown.