Why is cross-teaming so openly allowed?

[Combirdable]

I don't care if a team has more players it isn't okay to cross team like its practically encouraged and unless they have unfair advantages like exploits or hacks their is no reason for it to be allowed. I hate that you see it in every match at this point and if you think it's okay you are part of the problem. The game works were their are 4 teams, not 4 teams but if one is doing better, it's all against them.

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