Betting on games that you don't have much idea about can be very risky but staking low can be a way to play safe because the chances of losing is very high.
Why we should bet on the games that we don't really understand? If we have no idea on the games, it is better to ignore them. So far, I never try betting on the games that I'm not familiar enough. Besides the chance to lose higher, it is also less of fun. I think most people must choose the games that they have a bigger chance to win. And we probably prefer to bet on our favorite games.
Sometimes bettors don't look into the details of some matches, there are times when stats shows that the underdogs has more chances of winning
Each bettor may have their own way. But I personally will always look into the details of all the teams.