If it's unclear to anyone, eliminating [or striking] jurors for cause is not the same as one side exercising a strike.
As we are seeing, they interview (aka voir dire) the potential jurors, and as they go some are dismissed because they are deemed BY THE COURT to be unsuitable for some legal reason. These are the requests as they go to dismiss Juror X or Y "for cause" -- ie, one side or another is suggesting that they do not meet the legal standard for a juror for this case. Or the judge just unlaterally does it. It may be bias, it may be too much case research, it may be that the juror has potential conflicts, it can be any number of things that are discovered in the questioning. Whatever it is, one party is wanting the court to exercise its latitude and eliminate that potential juror. The judge makes the call, and there is NO LIMIT on how many jurors can be eliminated for cause.
Eventually they will get up to 30 or so that are deemed legally acceptable to be jurors in this case by the court.
After that, the 2 sides will be able to strike jurors, and assuming they do it like here, they will start with Juror 1, each side will be able to strike him/her if they wish, and each side can continue to strike jurors up to a certain number of allowable strikes each side has been given. When they have the first 12 who were not struck, they have their jury. In my math, that gives each side 9 or so strikes, but whether either side uses all 9 is up to them.
Hope that helps.