I have not played football since the 9th grade. I've not played baseball since the 8th grade.  I played Soccer, Hockey and basketball (and some other stuff here and there).

No one was stealing our plays or signs in football or baseball at the level I was at.  And if you were doing that, it would have undoubtedly resulted in some type of penalty for football (would have been weird), and in baseball it is against the spirit and comes with consequences.

So I'm just wondering when did "sign stealing" become so common, but seemingly, acceptable?  Is it at all levels, or just the big time levels?  My personal opinion is it's called "stealing" for a reason, and it's quite rare to see that word being used in a positive light.  Stealing is most generally considered unethical, unless you're "stealing a base".  

In listening to this Douchebag Stalions discuss his career from the military, when this began, all the way to Michigan, at what point does it just become a normalized thing that everyone accepts?  If someone asked me to "steal" signs I would 100% say "no chance I'm doing this."  It would just seem wrong.  But apparently it's "accepted" now.

When and why did this become acceptable?