It is only in sport betting that the manipulation is not there because it is a live match which mean you play according to your mind with a believing luck.
This isn't true at all. There have been plenty of cases where sports events were proven to be rigged/fixed primarily for the sake of money. Examples include volleyball matches, cricket matches, table tennis events etc.
Such rigged cases usually popup in lower leagues for obvious reasons based on my research.
Well, when it comes to rigging a match, that is also known as match fixing, then this is very real and I don't think there should be anyone In gambling who should not already know this possibility.
But like you said, rigging in sports events is not something that is very common, most especially with big leagues, it is mostly common among the very small up and coming league, who are easily tempted and probably cajoled into doing this for the sake of making money.
For a gambler who does not want to risk losing money unnecessarily on fixed, rigged matches, then such a gambler may want completely avoid betting on games played by small leagues, for it is very difficult or even impossible to know matches that are fixed, rigged without the help of an insider.