In a normal economy you are 100% right, the price increase is a symptom of the problem. However if you increase your prices because you think the inflation will be a certain level, then the increasing prices are not only a symptom but also a cause...Price controls are not, never were and never will be a viable way to combat inflation. Also, rising prices is a symptom of the problem, not the cause. To combat inflation you need to go after the cause, which are:
1) Money printing
2) Unbalanced public budgets