Look at it this way:
There are 3 standout teams in a regional. Let's just use A, B, and C. Suppose A is dominating in their qualifying matches. B and C start off the competition the same way and it is a battle for first place. Oh no! B's robot breaks down, they have a bad match, now they are essentially a match behind A and C in the rankings. If A and C continue to perform, they have no chance at the number one seed they wanted.
Time for B to tank some matches. Show that they have potential but make sure that they seed outside of the top 4(or whatever it is) so that now whoever is the number one seed can pick them. Your method does do something for the excitement elims but it would lead to teams throwing away qualifying so that they can still win the regional.
If you want to look into it there was a actually a similar problem several years back with high level badminton. Teams were purposefully losing (quite obviously, a pro team can definitely serve it over the net) because it was actually to their advantage to lose.
Article:
http://www.nytimes.com/2012/08/02/sp...ches.html?_r=0