Playing for points: is it really that bad?

I often hear a lot of BJJ coaches dissuading students for playing for points. By " playing for points" I mean where a BJJ practioner attempts to control their opponent, gain dominate positions and in doing so score points to win matches, without making serious attempts to submit their opponent.



Some reasons I've heard bjj coaches favouring always going for submissions are:



1) "It's better for self defense to always look for a quick submission"



2) "if you don't tap your opponent quick they might come back and tap you"



Are there any more reasons why playing for points is a bad habit to get into?



I'm not convinced on the point about self defense. First of all, I can think of a bunch of reasons why trying to submit an attacker on "the street" might be a bad idea. Secondly, some submissions I know just aren't practical outside of a bjj sports context.



Surely if your game involves strong take downs, strong guard passing, strong controls from back/side/mount and strong escapes, that can have a lot of value in a self defence context?



Any other thoughts welcome!